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Magnets in transmission pans and oil drain plugs help capture ferrous metals, but how do you know when debris is a sign of trouble? Andrew Markel explains the role of these magnets, what they collect, and how to determine if a transmission or engine issue may be developing. Learn key insights for better maintenance and diagnostics.
This video is sponsored by Auto Value and Bumper to Bumper.
The post Magnets and Drain Plugs appeared first on Brake & Front End.
The second-generation VW Touareg hit the road in 2011 and finished its production run in 2018. Aligning this Touareg is very similiar to the previous generation. Previous-generation Touareg models had uneven and rapid tire wear problems. The second generation is not known for this issue.
Precautions
The Touareg is not your typical vehicle to align. It has a stability control system that needs a recalibration of the steering angle sensor if the toe front or rear is adjusted.
On vehicles with air ride systems, lifting the vehicle for a repair requires that the vehicle lift mode must be activated. The vehicle lift mode switches the air suspension control off. This prevents readjusting of the air springs when the vehicle is lifted. Vehicle lift mode is automatically switched off at a speed above 3 mph.
Use the following procedure to deactivate the air suspension:
1. Switch on the electrical parking brake.
2. Switch on the ignition.
3. Press the LOCK button in the center console for 5 seconds.
The “Vehicle Lift Mode” is displayed in the instrument cluster and the indicator lamp in the LOCK button flashes.
Inspect the tires before alignment. According to VW, the tread depth difference may be no more than 2 mm on an axle. Also, the service information says a wheel alignment should not be done until the vehicle has been driven 1,000 to 2,000 km (621 to 1243 miles), since it takes this long for the coil springs to settle.
Front Suspension
At the front of the Touareg is a double wishbone with a tall knuckle. The suspension can have either air or coil springs. The lower control arm inboard mounts have factory-installed cam bolts to adjust the camber and caster. The front lower cam bolt adjusts camber and the rear bolt adjusts caster.
The most common failure on these models is the lower shock bushing. Upper control arm bolts are torque-to-yield with a torque spec of 50 Nm and a turn of 180 degrees.
Rear Suspension
The rear suspension is a multi-link setup with a large lower control arm. Toe is adjusted with the toe link and camber is adjusted using the cam bolt in the lower control arm.
If the rear tires have inner edge wear, inspect the bushings for damage. Most likely, the bushing that attaches the knuckle to the lower control arm is damaged.
Back in the day, a non-directional rotor finish was the method used to solve a common problem that occurred on bench brake lathes. If the crossfeed speed was too fast, the rotor became like a vinyl record, and the pads became the needle that followed the grooves in the record. This would cause a clicking noise as the pads moved in the caliper as it followed the concentric grooves.
The solution was to apply a non-directional finish. A non-directional finish breaks up the grooves cut by the lathe. These are typically cut with a rotating abrasive disc that moves across the face of the rotor. The finish looks like cross-hatch marks on a honed cylinder. In the 1970s and 1980s, the pages of Brake & Front End had ads for lathes accessories to apply a non-directional finish.
Why was it such a big deal? The reality was that the crossfeed on some lathes was set to what was used for drum brakes. The faster setting made more pronounced concentric grooves on brake rotors. Typically, the solution was to reduce the crossfeed speed to reduce the grooves. Also, many floating caliper designs were not great at holding the brake pads steady in the bracket.
Today, non-directional finishes on new brake rotors still serve the same purpose, but they also help in the bedding of some friction formulations.
The surface finish of a new or resurfaced rotor should meet OEM specifications for good braking performance, pedal feel and quiet operation. Brand-new OEM rotors and aftermarket rotors from a quality supplier typically have a surface finish that can vary from 15 to 80 microinches. Most brake experts say the best finish is 50 microinches or less, though a finish in the 60- to 80-microinch range is acceptable.
When a rotor is turned on a brake lathe with sharp bits (we emphasize the word âsharpâ because it is absolutely essential for a quality rotor finish) and a feed rate that is not too fast, the rotors will have a finish that meets these recommendations. Dull bits and fast feed rates tear chunks of metal from the rotor, instead of properly cutting it as they should.
If you turn your rotors with sharp bits and the proper feed rate and depth of cut, using a hone to apply a non-directional finish can help to reduce noise and shorten burnishing times.
As a final step, any rotor should be cleaned so metal debris, oil and anti-corrosion chemicals are removed from the braking surface. Not washing the rotors after they have been turned can leave a lot of junk on the surface that can embed in the pads and possibly cause braking issues, as well as noise when the rotors are installed.
NON-DIRECTIONAL FINISH TECHNIQUES
Non-directional rotor finishes can be applied in a number of ways. One way is by using an abrasive disc in a drill or a special rotor refinishing brush. As with the sanding block, you want to give each side about one minute of sanding while the rotor is rotating on the lathe. Also, follow the manufacturerâs recommendation for rotational speeds. Another method is to hold a pair of sanding blocks wrapped with 120-grit sandpaper firmly against both sides of the rotor for about one minute while it turns on the lathe.
Sanding knocks off the sharp peaks on the surface of the rotor and generally improves the surface finish by 15 to 20.
WHAT REALLY CAUSES NOISE
A non-directional finish can reduce initial break-in noise and help suppress noise for a while; however, brake noise can still occur if there are vibrations between the pads and rotors.
Brake squeal is caused by undampened high-frequency vibrations. When the brakes are applied, and the pads contact the rotors, tiny surface irregularities in the rotors act like speed bumps, causing the pads to jump and skip as they rub against the rotors. If the pads are not dampened by shims (external or internal) or are loose in the caliper mounts, they shake and vibrate and may produce an annoying high-pitched squeal.
The vibration of the pads against the rotors can also create harmonic vibrations in the rotors that cause them to ring like cymbals. Depending on the metallurgy of the rotors and the design of the cooling fins, some rotors may ring louder than others, regardless of the type of surface finish.
So, even if you do everything right, you can still end up with a noise problem if the pads or rotors themselves are inherently noisy. Switching to a different brand of brake pads or substituting a different type of friction material may be necessary to get rid of the noise.
A tip for reducing noise-producing vibrations is to apply a high-temperature brake lubricant to the backs of the pads and the points where the pads contact the caliper. Lubricating the caliper mounts, shims and bushings is also recommended to dampen vibrations here, as the lubricant acts as a cushion. It also helps the parts slide smoothly so the pads wear evenly (uneven pad wear is a classic symptom of a floating caliper that is sticking and not centering itself over the rotor).
The type of rotors used on the vehicle can also affect noise. Some grades of cast iron are quieter than others. Thatâs one of the reasons why composite rotors have been used on various vehicles over the years. Besides being lighter, composite rotors can also be quieter when the right grade of cast iron is used for the rotor disc. Replacing a composite rotor with a solid cast-iron rotor changes the harmonics and frequency of the brake system and may increase the risk of brake noise on some vehicles. Also, some low-price rotors may use a lower grade of cast iron that is noisier than the OEM rotors they replace.
While it’s common for a customer to bring us a vehicle with a single, specific complaint, we often find more than one problem when getting into the diagnosis of their original concern. The owner only knows one thing; they want the vehicle to run and operate properly. It’s our responsibility to identify and execute a complete repair and convey what that entails to the customer.
Case study 1: 4R75E
Today’s story begins with a 2006 Ford F-150 equipped with a 5.4L engine, 4R75E transmission, and 434,000 hard-use miles. The customer’s concern was simple: The overdrive light was flashing, there were hard shifts in every gear, and the transmission malfunction indicator was illuminated on the dash. The customer provided the following trouble codes to us: P0705 (transmission range sensor circuit fault), P0748 (pressure control solenoid electrical), and P1702 (transmission range sensor circuit intermittent fault). He told us that the transmission had been rebuilt a year previously, and had never worked correctly since that time.
I began the evaluation by checking the fluid level and condition to see that it was full and fair. A quick code scan before the road test revealed that a lot more was going on with this vehicle beyond what the customer shared with us. A laundry list of engine performance codes was stored in memory along with the three that were provided by the customer. During the road test, I was able to confirm the hard shift in every gear complaint but also noted engine misfires present and a lack of power once warmed up. During the under-vehicle inspection, it appeared that the range sensor had been replaced at some point.
At this point I recommend electrical testing to pinpoint the cause of our range sensor and pressure control problems. Our service writer explained in detail that there was more than one issue on the vehicle and that it would take extra time to pin down properly. The customer approved the additional diagnostic time, so I rolled up my sleeves to dig into it.
I started with the range sensor codes. After checking power and ground down to the connection, range sensor voltages seemed normal but were out of sequence per the wiring schematic. TR2 should have had 12V present, but only showed 5V. TR3A, on the other hand showed 12V when it should have been 5V—very puzzling. I pulled the wiring loom off and discovered that the pigtail for the range sensor had been replaced as well. I removed the face of the connector and swapped pin 3 and pin 5. (See Figure 1, above).
Checking from the PCM connector down to the range sensor connector proved the wires were simply in the wrong position inside the connector. I cleared the codes, and the range sensor codes never came back during the road test, but I still had the hard shifts and overdrive light flashing. This meant it was time to move on to our apparent pressure control issue.
I began by disconnecting PCM connector C175T and checking for voltage on pins 38 (vref), 37 (ssb), 36 (tccs) and 39 (epc) with the key on. Pins 38, 37, and 36 all read battery voltage. When I got to pin 39, I found around 4V present. With that information in mind, I load-tested the wire from the transmission connector (pin 6) to the PCM (pin 39) to verify that I didn’t have a high resistance in the wire between the two. I suspected that the internal harness of the transmission had failed, but with the mileage of this vehicle, it was up to the customer to decide how further into this he wanted me to go.
Since the transmission had been rebuilt recently, the customer decided to have us replace the internal harness and pressure control solenoid before committing to a fully remanufactured transmission. After replacing the internal harness and EPC solenoid, the transmission worked perfectly, and the customer was pleased that we saved him the additional expense.
Case study 2: 4L80E
Our next vehicle was a 1999 Chevrolet Express 2500 equipped with a 5.7L engine, 4L80E transmission and 268,000 miles on the odometer. The customer’s concern was that the engine was stalling at stops and the transmission was shifting hard through its gears. The transmission had been rebuilt and started having problems eight months after that repair. The shop that had originally performed the transmission work attempted to diagnose these issues and had replaced multiple components before ultimately replacing the engine without solving the issue. Oops.
Upon starting the initial evaluation, I found the transmission fluid level low and in fair condition. A code scan revealed P0748 (pressure control solenoid electrical) stored. I pulled the vehicle into my bay to check for leaks before beginning a road test. As I pulled onto the lift and stopped, the engine chugged and stalled out. During the under-vehicle inspection, I found the transmission pan leaking. At this point, I stopped to talk with my service advisor because there was no leak concern noted by the customer. The advisor called the customer to confirm that he had been adding fluid to the van. I suspected that the stalling was caused by the low fluid condition present, so I topped off the transmission fluid and started another road-test. Even with the transmission fluid full the engine still wanted to stall when coming to a stop. When upshifting, the transmission shifted more firmly than it should with normal driving, but the shifts felt normal with heavy acceleration. The pressure control amperage on the scan tool seemed to be normal (around .7 to 1A, as seen in Figure 2).
Figure 2.
At this point it was clear to me that I may have more than one problem to diagnose on this vehicle. Our advisor got additional time approved, and I began my research.
Due to the hard shifting and P0748 code, I began by checking the circuit for the pressure control solenoid. When I inspected the PCM, I noticed that someone had spilled brake fluid on it when filling the master cylinder. I first checked the resistance in the circuit at the PCM C3 connector from pin 6 to pin 16 and found 4.5Ω, which is within specification. I then load-tested the wiring to make sure it could handle the current from the solenoid before putting my amp clamp on the circuit to prove what I already suspected. The current probe showed less than half an amp when our scan data showed around 1 amp. The pressure control solenoid was working properly, but the PCM had failed to control it properly. (See Figure 3).
Figure 3.
The customer was advised of our findings that the vehicle required a PCM replacement in order to correct the hard shifts, but that if the engine continued to stall, the transmission would also need to be replaced.
I replaced the PCM and that corrected the amperage issue to the EPC. (See Figure 4). Unfortunately, an internal transmission problem was evident after the PCM replacement, so we replaced the customer’s unit with our remanufactured transmission.
Figure 4.
After struggling with other shops to get the job done right, our customer was very happy to get the van back in working order except for one issue: now the headlights didn’t light up. After a few minutes of checking power and ground to the headlight connectors, we were able to confirm the sealed assemblies needed to be replaced, and the van was ready to get back to work.
You just finished a car or truck alignment or other repair that might have disconnected power to the vehicle. You pulled the vehicle off the lift and parked it in the lot. The customer pulls away and, within five minutes, they are back complaining an ABS, stability control or ADAS light is illuminated or a warning message is displayed. What happened?
When you scan for codes, you will find codes C1306, C1307 or another proprietary DTC indicating a malfunction with the steering angle sensor. Depending on the vehicle, these codes indicate a malfunction, inability to find the center or end stops, or missing calibration of the steering angle sensor.
Ninety percent of the time when a steering angle sensor code is active, it means the sensor needs to be calibrated. The other 10% of the time, the sensor has failed or there is an issue with the communication network sharing the data from the sensors.
The calibration process typically involves learning the center and end stops of the steering rack. Some systems require a static calibration in a bay with a scan tool attached. Others require a dynamic calibration which might need to be initiated with a scan tool. Other systems will perform the calibration automatically after a drive cycle.
If the calibration process can’t be completed, it will set a code for the steering angle sensor. Some proprietary codes will indicate why it aborted a steering angle sensor reset. If a code is not active, look at the datastream PIDs to see if the data changes when the steering wheel is moved.
If you are looking for the steering angle sensor data, it could be in several modules. Conventional systems connect the steering angle sensor to the ABS module, which is connected to a high-speed network like CAN. Vehicles with electric power steering typically have the sensors connected to the steering module that communicates with the engine control module to ensure engine speed does not drop when the driver turns the wheel. The steering module is connected to a CAN bus with the ABS and ECM. Another configuration might be to have a “sensor cluster” that communicates on the CAN network on its own.
The steering angle on your scan tool might be in degrees, but on some vehicles it could be a numerical value. Check the service information for the correct values. Most scan tools will have data from two steering angle sensors. Some vehicles will not use zero as the number for centered. Look at the service information. Also, some vehicles might require calibrating the motor position sensor that is located on the rack.
Engineers use two or three steering angle sensors in the column for redundancy and to double-check data. For some vehicles, the angle will have 180 degrees of difference. Other sensors that reveal data and codes are the yaw and lateral acceleration sensors. Dynamic-calibration vehicles will look at data from these sensors to confirm a change in steering angle results in a change in direction for the vehicle. If the sensor is not working or has active codes, a static or dynamic steering angle recalibration will not be possible.
On some vehicles, the steering sensor cluster is part of a module that may include functions for the turn signals, steering wheel, audio controls and wipers. This module is not a box, but part of the column and might have multiple CAN lines coming out of it. Often, the SAS cluster cannot be replaced on its own, instead requiring replacement of the entire unit.
ADAS CONNECTION
The steering angle is used by many ADAS functions, from blind-spot detection to autonomous driving. If the steering angle sensor is not calibrated, it could lead to the false activation of many ADAS systems. The most annoying malfunction is the false activation of the lane departure system. Even the smallest of errors in the SAS can make the vehicle think the driver is trying to steer into an oncoming lane. Some systems may just shake the seat, while other systems might try to steer the vehicle back into the lane.
One of the first items to be replaced on any Tesla model are the tires. This is due to tire wear from the instant torque of the electric motor. When replacing the tires, you will have to service the TPMS sensors.
Tesla has used Baolong (from 2012 to 2014), Continental (from 2014 to 2020 ) and a proprietary sensor that uses Bluetooth. For 2021, the Model Y started to use a sensor that communicates using Bluetooth protocols. Not much is known about the new system except that the sensors are currently available only through Tesla.
The Baolong TPMS system will not display the pressures on the center display. However, the Continental and Bluetooth systems will display the pressures for the driver. Tesla offers a retrofit kit to convert the Baolong system to a Continental system. The procedure involves replacing a module on the vehicle. Baolong sensors are available on the market, and aftermarket replacements can be programmed for the car.
Like many TPMS systems, the Tesla TPMS system has a built-in feature that automatically detects a new set of wheel sensors. The TPMS sensors can be reset via the vehicle’s touchscreen. The reset function is only possible when the vehicle is on.
Before starting, set the tires to the correct cold tire inflation pressure according to the door placard and tire size. Before servicing the tires, make sure the system is functioning.
Auto Learn
Turn the touchscreen on.
From the touchscreen, touch Controls > Settings > Service & Reset > Tire Pressure Monitor > Reset Sensors. Reset the sensors based on the wheel size. If a tire pressure warning displays, exit the vehicle, close the rear trunk and all the doors, wait for the touchscreen to go black, re-enter the car and ensure that the correct wheel size is selected before touching Reset.
Touch Reset, and then touch OK.
Press and hold one of the scroll wheels and select ‘Car Status’ to see an overview of the TPMS information. When the sensors are unknown, all the values will be shown as “- -”. Ensure that the vehicle is stationary for at least 20 minutes before continuing to the next step.
Perform a road test. Auto learning will start when the vehicle exceeds 25 mph. When auto-learning completes, the tire pressure information displays for all wheels and clears any TPMS faults. Note: Auto learning can take up to 20 minutes during a test drive.
Try this procedure again if “Tire Pressure System Needs Service” displays after performing auto-learning. If the warning still persists after 5 minutes of driving at 25 mph, further diagnostics might be required. This can include using a TPMS to verify the operation of the sensor.
Service Kits
Most Tesla models use service kits that have a clamp-on metal stem. A new service kit should be installed every time the tire is removed from the rim. The valve stem’s nut is a one-time-use item. Most kits are available in two finishes for silver and black rims.
Replacement Sensors
There are a wide variety of programmable 433-megahertz sensors for Tesla models. There are also direct replacement options.
What is up with the foam?
Some original Tesla tires have a layer of foam attached to the inside. This foam is designed to absorb noise from the engine or transmission. If there is a puncture, you can still repair the tire. You can cut the foam away from the area of the tire and use a patch. Just replace the foam section using cement glue.
1. Not cleaning the brake slides and hardware: Just slapping new pads and abutment clips where the old ones once resided never works. The caliper bracket slides need to be clean and free from rust. Don’t get overly aggressive with the wire brush. Some automakers are using anti-corrosion coatings and surface treatment on the brake caliper bracket lands. If brake cleaner and a nylon brush can’t tackle the deposits, you might be making the corrosion worse by using a wire wheel or file.
2. Not lubricating the guide pins: This is a shortcut most pad slappers make. Caliper guide pins on floating calipers should always be cleaned in solvent and new grease should be applied. The grease is under extreme heat and pressure, so always use caliper-specific grease. NEVER put a torn boot back on a car. Failure to service the guide pins is the leading source of uneven pad wear. Also, avoid using impacts to remove or install the guide pins. Most guide pins are plated with an anti-corrosion material. Spinning the guide pin in a bore could damage the plating.
3. Installing the brake pads backwards: It happens more often than you would think! You may get a car in your shop with the owner complaining that the brakes are grinding after a “friend” changed the brake pads.
4. Not measuring the rotor: Rotor thickness and runout needs to be measured every time. Running a rotor that is below specifications can cause safety issues like cracking and fading. Also, not correcting lateral runout can lead to a pulsation complaint.
5. Not machining the rotor: New pads almost always require a fresh rotor surface so the pads can deposit a thin layer of friction material to increase braking performance. If old deposits of the previous material are on the rotor, it can contaminate the new pad and lead to performance and noise issues.
6. Not properly torquing the caliper bracket bolts: Not all caliper bracket bolts are the same. Torque ranges can vary from 30 to 110 ft./lbs. Also, some bracket bolts can be torque-to-yield or require liquid tread lockers. If you see an aluminum knuckle, look up the torque specifications.
7. Over torquing the caliper guide pin bolts: Caliper guide pin bolts typically need a 13 mm wrench to remove. It is a rookie mistake to go nuts on these bolts and break the heads off. Typically, these bolts require only 25 to 35 ft./lbs. of torque. Be gentle!
8. Installing a caliper upside down: Nothing is worse than going to bleed a new set of calipers on a vehicle, only to find the bleeders are on the bottom of the caliper and not the top. The bleeder needs to be at the top of the caliper to remove all the air. Always check the box to make sure you have a left and a right before you start the job.
9. Using cheap brake pads: The most common mistake for rookies is to shop for a pad on price and not quality, features and reputation.
10. Hanging the brake caliper by the hose: Nothing is more painful than to watch a brake caliper do a bungee jump from a control arm or knuckle and see it dangle by the brake hose. This can cause damage to the internal structure of the hose, which can cause a soft pedal or a rupture.
The anti-lock braking system (ABS) computer, or HCU, is a node on a high-speed vehicle bus. This means that the information can typically be accessed through the OBD-II DLC.
The ABS controller/modulator is the heart of any ABS or ESC system. The modulator gets the brake pressure from the master cylinder. Located inside are the valves and solenoids that control the pressures to the wheel. During normal operation, the pressure from the master cylinder goes through the HCU unaltered.
ABS is the foundation of the ESC system. ESC systems add software and sensors like yaw, steering angle and even throttle control to keep the vehicle under control.
A basic ABS four-channel system will have eight solenoids (four isolation/four dump), or two for each wheel. Some systems will have more solenoids or valves to isolate the master cylinder from the HCU. ESC systems will typically have 12 or more.
Apply
When the master cylinder applies pressure, it goes directly to the wheel because the outlet/dump solenoid is closed. This is a normal braking event. The unit is in a “passive” state.
Hold
If the system senses a wheel is locked, the inlet/isolation solenoid is closed to prevent any more pressure from the master cylinder from reaching the wheel. The wheel might start to turn.
Release
If the wheel does not start to turn, the outlet/dump valve will open. This will release or bleed off the hydraulic pressure that is holding the wheel. The wheel will now rotate.
Reapply
Since pressure from the master cylinder has been bled off, the pump in the HCU will spool up and apply pressure. The outlet valve is closed and the inlet valve is opened. The pump applies pressure to the wheel.
If the wheel is still outside the wheel slip parameters, the cycle will start over. This happens very quickly.
On older systems, the operation of the solenoids and pump will cause a “kick back” or pulsation in the pedal. Modern systems are able to minimize the kick back through valves that isolate the master cylinder from the HCU.
HCU Mechanical Problems
Mechanical issues with the HCU are rare, but they can occur. Valve seats and pintles can become stuck or not seat properly due to debris, corrosion or contaminated brake fluid.
If the inlet/isolation valve is stuck open, it will not affect normal braking in any way. It will hurt only the ABS system. This could lead to a pulling condition during ABS activation.
If an outlet/dump valve is stuck open in one circuit, this could cause a pull condition during normal braking. This is due to the loss of brake pressure at a wheel. Typically, this is not discovered until brake hoses, calipers and other parts have been replaced.
Testing Solenoids Electrically
Sometimes a stuck or defective solenoid or pump will set a code. A solenoid has a resistance between 2 and 8 ohms. On some units, it is impossible to access the individual solenoids. Testing the unit with a scan tool with bidirectional control might be the best way to confirm the condition of the HCU.
Most vehicles equipped with ESC will have 12 valves or solenoids in the HCU. Eight solenoids control the wheels. Four additional solenoids can block off the master cylinder and allow the pump to send pressure to a specific wheel.
Understeer is a condition where the wheels are turned, but the vehicle continues to travel in a straight line. This is sometimes described as a push.
The ESC computer would see this event through the sensors. The wheel speed sensors in the front typically read slower than in the rear. The computer also would see that the steering angle is greater than the intended path.
The ESC system needs to intervene before the event occurs, and it needs to anticipate the problem and correct it as the vehicle travels.
This is what the ESC sees during an understeer event. The SAS angle is at +52º, which means that the customer has the wheel turned to the right at a significant angle. Even with the steering wheel turned, the yaw and accelerometer read like the vehicle is going straight. The APPS, or accelerator pedal position sensor, shows the driver is off the gas and the brake pedal is not pressed.
The deciding information for the system is in the wheel speed sensor inputs. There is a 6 to 9 mph difference between the front and rear speeds. The front wheels are traveling slower than the rears.
Why Brake Lines Fail During Winter
Winter is when the ABS HCU has to do the most work to make sure the tires have traction during braking and acceleration. When the ABS activates, the pulsing of pressure can create a hydraulic jackhammer. If a line is weak due to internal or external corrosion, it will cause the line to rupture and leak.
Rock salt and deicing brines can corrode brake lines. Automakers have tried galvanization, polymer coatings and physical barriers to stop this corrosion, but these surfaces can’t prevent age and the pecking of road debris from causing corrosion. A hydraulic brake system is only as strong as its weakest connection. Splicing together corroded line does not work in most cases, and replacing just the leaking section will result in a comeback. The best practice is to replace the hard line from the wheel well with an undamaged line. On vehicles with coated line, you must find the area where the coating is still intact.
Another factor influencing brake line replacement is how modern cars are manufactured. In most cases, the brake lines are installed on the unibody, and the subframes for the suspension are fastened to mounting points. Most of these lines are one piece and will go from the HCU or subframe connector to the caliper.
Installing a pre-bent line might be cost prohibitive for the customer because major disassembly is required. One option is to use tubing that can be formed in place. Or, pre-bent tubing can be cut into sections so it can be maneuvered into place without having to remove the subframe. The placement of brake lines is not coincidental.
With ABS-equipped brakes, never take a flare for granted. To seal brake lines against 2,000 psi takes some geometry. The male and female surfaces of the fitting are three to five degrees different between the sealing surfaces. In some cases, the flare is designed to crush or compress onto the surface to form a seal, and the tolerances can stack up quickly against you. An off-center cut combined with a poorly clamped line may look fine to the naked eye, but the connection may leak when it is compressed by the fitting.
If you install new brake lines on a modern ABS-equipped vehicle, you will need a scan tool to bleed the brakes. Air bubbles in the system can occur in the modulator body if the system has lost all of its brake fluid. Removing these bubbles may require the use of a scan tool to open up the isolation and the dump valves in the modulator.
New vehicle ADAS and autonomous features all rely on the alignment being exactly as it should by OEM specifications for the driver-assist features to perform correctly.
Vehicle alignment has always been a critical piece to the repair and safe operation of any vehicle. In years gone by, we all experienced a customer who would return after repairs were completed with concerns about the vehicle pulling or not staying in the center of the road. Although it happened, it was not all that common because any issues that would affect the alignment were usually found during the repairs.
Today’s vehicles shine a whole new light on how important a vehicle’s alignment is. The new advanced driver-assistance systems (ADAS) and autonomous features on vehicles all rely on that alignment being exactly as it should by original equipment manufacturer (OEM) specifications for the driver-assist features to perform correctly. It is not just about going straight down the road anymore; now, the vehicle’s attitude or alignment to the roadway is also a factor.
Is an Alignment Needed?
This brings to light what to do if the repairs do not warrant an alignment. Think about this scenario: A car is traveling across a parking lot at a low rate of speed. A collision occurs with a pickup truck that causes light damage to the front bumper cover and grille. In that bumper cover behind the grille is the radar for the adaptive cruise control. The bracket that holds the radar is bent, requiring replacement.
Let’s assume all other aspects of the bumper cover are repairable, according to OEM parameters. Following all of the OEM repair procedures, it’s noted that a calibration of the radar is required due to the bracket being replaced – which required the radar to be disconnected, removed and installed (R&I).
The shop reads through the OEM prerequisites to do the calibration for the vehicle. These include (depending on the vehicle manufacturer):
Fill the fuel tank to full;
Fill all fluid levels;
Correct air pressure;
Have the proper tires and wheels for model of vehicle;
Verify the alignment;
Verify the steering wheel angle sensor is correct.
There is more I can add, but you get the point that there are required preparations of the vehicle prior to doing a calibration. Also, to do the static calibration, there are environmental requirements, such as level floor or – for dynamic calibrations – weather conditions.
During the calibration, a drive cycle is performed to verify that all systems are operational and it’s found that the vehicle is out of alignment and the calibration fails. The alignment issue is not the result of the damage from the collision that was repaired.
To complete the calibration required for the repairs and procedures that were performed, an alignment must be done. Who’s responsible for the cost of that alignment? It’s a question that’s coming up in many shops across the country. This is not a bent or broken part that’s unrelated prior damage that’s easily pointed out to a vehicle owner; this is a simple condition of the fact that vehicles can be out of alignment just from daily commutes every day.
Another question pops up from the prerequisites: Who pays to fill the tank with gas? Interestingly enough, I’ve asked many shops and insurance companies this question and gotten a lot of different responses. Some said the alignment may or may not be covered, but it was interesting that almost all said “no” to the tank of gas.
Covering the Cost
Let’s look at another scenario: An owner takes a vehicle to a technician because the vehicle is wearing the tires unevenly. It’s found that the vehicle needs an alignment. The parts and labor are the responsibility of the vehicle owner, as this is a general maintenance issue. It’s also found that the vehicle will need to be calibrated, since the alignment changed the vehicle’s attitude to the roadway. Now, the calibration must be added to the repair. The cost of doing the alignment has now increased tremendously for owners of vehicles with ADAS.
We know that the vehicle maintenance of any motor vehicle is a cost the vehicle owner must pay, as no insurance claim is involved. However, we’ve all learned over the years that the lines get muddled when a third party is covering the cost. When a third party is involved, the key phrase “repair to pre-loss condition” is all a party is required to pay. Unrelated prior damage or even maintenance issues on vehicles that have an effect either on the repair itself or the safety of the vehicle have always been a problem in the repair industry. Nobody wants to put a vehicle that is unsafe or dangerous back on the roadway.
High deductibles and procedures not covered by insurance is money many people are having difficulty with. I know this varies from city to city and from different companies or third parties who are paying for the vehicle repairs, but whether it be a bad part, an adjustment to toe or a steering wheel angle sensor procedure, the need for the alignment to be within specifications is more critical than in the past. We, as an industry, need to be prepared to have more conversations about customers paying for alignments and calibrations and their prerequisites. Many shops are adding signage or verbiage to make consumers aware that fuel charges, that the owner will be responsible for, may be added to the costs.
Releasing a vehicle with the safety features compromised or disabled is not an option a shop should pursue. Not following all the guidelines necessary for a proper calibration will bring the shop a whole new level of scrutiny that it will not want if the unfortunate event of a crash occurs.
Let’s say the alignment was not done or verified to be correct and the customer comes back with a drivability complaint. Who is responsible for the costs to complete the alignment now? Remember hearing, “Well, it was not like that before you fixed my car.”
A warranty is never good for any shop, as it costs the shop money to have an alignment done – whether it is in-house or subletted out – and upsets workflow. Add to that the fact that the customer is now not as happy as he or she should be with the vehicle repairs and is spending time getting it corrected. This can have a demoralizing effect on shop management and your team. No technicians want to do repairs or warranties for free, even if it is to make the customer happy.
The Blame Game
Another growing trend is the vehicle’s owner’s manual states that the driver has ultimate responsibility in the operation of the motor vehicle. In today’s new society of “nobody is responsible for anything that happens,” if a vehicle were to be involved in a crash, I can see people wanting to blame the last person who repaired the vehicle’s safety features: “My car did not do what it was supposed to do.” Doing a calibration in the parking lot or not verifying the alignment can make a jury overrule the owner’s manual or side with basic common sense. Even if nobody, such as the third party or customers themselves, will step up to the plate and pay, can you afford to be uncertain whether the vehicle is compromised when it leaves your shop?
Summary
The alignment issue has been a problem for a while now in many aspects of vehicle repair. To verify an alignment, you’re basically required to actually do the alignment.
The good news is new tools are being developed that are capable of doing quick checks on a vehicle’s alignment. This is valuable to all shops doing body work, mechanical or auto glass. Instead of doing an alignment or setting up the vehicle on an alignment rack, these tools can be used right on the level floor of the shop, saving setup time and labor. This will become a big item for the auto glass industry, which currently does not even address the requirements for verifying alignment; the windshield is replaced and possibly calibrated, then out the door it goes. AUTEL, Hunter and Bosch offer systems that do quick checks on alignments for body shops and auto glass replacement companies.
Educating vehicle owners and the public on the processes and procedures to repair vehicles is a must today. Spending time explaining and informing every customer of what it takes today to repair a vehicle is not the same as yesterday … and these conversations may help to ease into who pays for what in the new world of automotive repair.