Archives 2024

Understanding Electric Vehicle Drive Units: Components, Functionality, and Maintenance



The Core of Electric Vehicle Drive Units

This complex system consists of various components that work together to deliver the power and torque required. Unlike their gasoline-powered counterparts, electric vehicles (EVs) rely on an electric motor and a battery pack to propel the vehicle forward. EVs operate at high voltages, typically ranging from 300 to 800 volts, to power the electric motor(s) and other components. Proper safety protocols and specialized training are essential when working on or around the high-voltage systems in an EV to prevent serious injuries or damage.

At the core of an EV is the drive unit, which is responsible for converting the electrical energy stored in the battery into the mechanical energy needed to move the wheels. This complex system consists of various components that work together to deliver the power and torque required.

The electric motor is the primary component of the drive unit, converting electrical energy into mechanical energy. These motors come in various types, such as AC induction motors, permanent magnet synchronous motors, and switched reluctance motors, each with its own unique characteristics and performance capabilities.

The power electronics module, often referred to as the inverter, is responsible for controlling the flow of electricity between the battery and the electric motor. It converts the direct current (DC) from the battery into the alternating current (AC) required by the motor. The gearbox, or gear reduction system, is responsible for transmitting the high-speed, low-torque output of the electric motor to the wheels, which require high torque and lower speeds for efficient and effective propulsion. This gear reduction system typically consists of a single-speed or multi-speed gearbox, depending on the design and performance requirements of the vehicle.

To ensure the efficient and reliable operation of the drive unit, a sophisticated cooling system is in place to dissipate the heat. A network of sensors and control systems continuously monitor the performance of the drive unit, allowing for real-time adjustments and diagnostics.

While EV drive units are generally more reliable and require less maintenance than their internal combustion engine counterparts, they are not immune to issues. Common problems may include bearing failures, gear wear, cooling system malfunctions, and electrical component failures.

Maintaining an EV’s drive unit is crucial for ensuring its longevity, performance, and efficiency. Unlike internal combustion engine vehicles, electric vehicles have different fluid requirements for their drive units. These fluids, such as lubricants and coolants, are specifically formulated to work with the components and operating conditions of EV drive units.

The recommended service intervals for EV drive units can vary depending on the manufacturer, driving conditions, and usage patterns. Generally, it is advisable to follow the manufacturer’s guidelines for scheduled maintenance, which may include regular fluid changes, inspections, and component replacements.





Automotive

Our Gift To You – ShopOwner’s Digital December Issue


The interactive and easy-to-use digital edition of ShopOwner’s August issue, featuring articles from Brake & Front End, is available now.

Click Here to read the August issue

In addition to management topics and opinion pieces, you’ll learn about the challenges of aligning the VW Touareg; tips to make aligning ANY vehicle easier; how to discover new data available from the brake pedal; and more.





Automotive

Steering Angle Sensor Operations



Measuring the steering wheel position angle, rate of turn and torque applied by the driver are typically the job of a sensor cluster that contains multiple steering angle sensors (SAS).

The sensor cluster will always have more than one steering angle sensor. Some sensor clusters have three sensors for redundancy, for improving the resolution of the sensor cluster and to confirm the data. It is important for the ABS/ESC module to receive two signals to verify the steering wheel’s position. These signals are often out of phase with each other.  

Analog SASs are similar to throttle position sensors. SASs are wired with a 5-volt reference, chassis ground and signal output. To test the SAS, you have to backprobe a connector that is typically under the steering column. 

As the steering wheel is turned, the SAS produces a signal that toggles between 0 and 5 volts as the wheel is turned 360 degrees. As the wheel is turned lock-to-lock, the voltage will reach 5 volts three times and 0 volts three times.

On most vehicles, turning to the right creates a positive voltage and to the left generates a negative voltage. But, some systems are the opposite. The labscope pattern shows the signal traces from the two sensors on top of each other. This can be helpful when comparing the signals and if one is flat lining.

A digital SAS is often called a “contactless sensor.” This type of sensor uses an LED light, a wheel that acts as a shutter and an optical sensor that measures interruption in the light. The signal for these types of sensors is a digital square-wave signal. The frequency of the voltage changes depending on the speed the wheel is turning.

The sensor clusters for these sensors often contain a third sensor to measure if the wheel is centered. With the wheel straight, the voltage is close to 0 volts. When the steering wheel is moved off center, the voltage goes high.

Some scan tools will display the data as an angle. In some cases, you can see the voltages from the sensors.

Torque Sensor

Measuring the amount of force being applied by the driver to the steering wheel is used by both the stability control and power steering systems. The information can be used to determine driver intentions and the performance of the power steering system. But, it can also detect a steering pull.

The torque sensor performs the same function as the torsion bar and spool valve in a hydraulic system. The electronic sensor uses a torsion sensor in the same manner as in the spool valve in a hydraulic power steering system. There are different types of electronic torque sensors, and they are classified as contact and non-contact types.

Steering Sensor Clusters

Most vehicles mount the steering angle and torque sensors in a single module on the steering shaft. Some call it a steering sensor cluster. The module connects to a Controller Area Network (CAN) bus. On some vehicles, it can connect directly to the ABS/ESC module. 

Resetting Sensors

Many vehicles require the SAS to be reset or recalibrated after an alignment is performed (even if the rear toe is adjusted) or components in the steering system are replaced. There are three types of reset procedures:

  • First, systems that self-calibrate on their own. 
  • Second, vehicles that require specific wires to be grounded or buttons be pressed. 
  • Third, systems that require recalibration with a scan tool. 

Even if the SAS is out of calibration, most vehicles have ways to sense if it is traveling in a straight line. If the angle is far enough out of range, it might set a trouble code and disable the ABS and/or ESC system.

Self-Calibration

On some import vehicles, recalibrating the sensor after an alignment or if the battery has died is just a matter of turning the wheels lock to lock, centering the wheel and cycling the key. This “auto learn” functionality is becoming more common on newer vehicles.

Scan Tool Steering Angle Sensor Reset 

There are many options for scan tools to reset steering angle and torque sensors. Some tools are even integrated into an alignment system. But, most tools recommend that the calibration be performed on a level surface. This is because you are also calibrating the yaw and accelerometers. 

Also, it is always a good idea to perform a lock-to-lock steering wheel turn to complete the calibration.





Automotive

Wheel Bearing Noise and Damage


When a driver hits a pothole or curb hard enough, extreme forces are put onto the balls or rollers and races of the bearing. This can result in the formation of a very small mark on the surfaces. The driver might go 1,000 miles or more before these components start making noise.

This damage is called Brinelling. This surface failure/defect is caused by contact stress that exceeds the material’s hardness limit. Brinell marks may cause the bearing to immediately make noise, and as the marks keep rotating, it could damage the entire bearing. If the impact is great enough, the preload on the bearing can change. This can lead to more damage and noise as debris finds its way into the grease. 

Hub Units

Hub assemblies are unitized, maintenance-free and non-serviceable parts that are preset, pre-greased and pre-sealed, easing installation and increasing product reliability for enhanced performance. These hubs require no maintenance or handling, which eliminates the need for preventive maintenance, grease and/or future adjustments.

Testing 

The first step in testing a bad bearing is an audio inspection. The typical sound associated with a bad bearing is a grinding noise that changes with vehicle speed while accelerating above 30 mph. A rumbling, growling, chirping or cyclic noise of any kind from the vicinity of the wheels is a good indication that the bearings need to be inspected without delay.

The most common method of testing wheel bearings is to lift the vehicle and grab the wheel at the 12 o’clock and 6 o’clock positions to feel if there is any noticeable play. By grabbing the wheel at these points, any play in the steering system is eliminated. But, with some hub units, the failure tolerance may be so low that a bad bearing is undetectable by this method. In these cases, a dial-runout gauge could be your best friend. 

Replacement

A high-quality bearing is key for performing a comeback-free job. High-quality hub units or bearings typically use higher-quality materials and heat-treating processes that make for harder surfaces. The harder surfaces will not Brinell under hard impacts. 

When replacing a hub unit, the replacement unit might feel stiff and difficult to turn. Do not return the bearing. Some hub units and sealed bearings are pre-filled with a special grease that prevents damage while the bearing is being shipped. The grease is designed to have a high viscosity during shipping so the balls or rollers do not destroy the surfaces of the races. After the bearing is installed, certain elements in the grease break down to allow the bearing to turn normally.

Removing some hub units may be very difficult due to corrosion. This can be the case more frequently on vehicles with aluminum knuckles. In some cases, it might be necessary to press the hub from the knuckle off of the vehicle using a puller.

Once the old bearing has been removed, take the time to clean and inspect the bearing bore and axle surfaces that make contact with the bearing. Any debris or imperfections can prevent the bearing from seating properly.

Check the bore for roundness using a snap bore gauge. The gauge should easily rotate in the bore. Any distortion in the bore can cause a new bearing to fail prematurely. It can also make installing the new bearing to the proper depth impossible. 

While it may appear to be easier to use an impact wrench, it is not recommended. OEM and bearing manufacturers always recommend using a torque wrench for installation. During removal, an impact wrench can damage the axle nut threads and shock the CV joints. It can also create a false sense of security when adjusting a nut or bolt, which may be under- or over-torqued. This can leave a hub assembly susceptible to failure. Also, in almost all cases, you should use a new axle nut. 

Connectors and Harnesses

It is not uncommon to pull a replacement wheel bearing hub with a three-feet harness out of the box. You might be tempted to splice the harness together to avoid removing brittle wheelwell liners. But, no matter how much solder and heat shrink tubing you use, the connection will not be as good.

It is critical that the harness be routed in the same way as the original. If a harness is not routed properly, it can become pinched between the brake and chassis components. Some new hub units include new clips and hardware.

On some vehicles, the wires tend to be brittle and break as a result of fatigue from road vibration and/or steering maneuvers. Replacing the wheel-speed sensor (WSS) wiring harness is usually the recommended fix for these situations. 

It is very difficult to repair WSS harnesses since the harness is in an environment that is exposed to water, heat and flying debris. The voltages measured by the next generation of wheel-speed sensors are so small that an alteration in the wiring can cause problems. This can lead to even more ABS diagnostic codes being set.

Some vehicles that use sealed hub units have the wheel-speed sensor and tone ring located between the bearings or on the inner seal. As the bearings wear out or are damaged, the air gap can change as end play increases. This change in air gap can cause “erratic” or “weak” wheel-speed sensor codes.

If you have a scan tool that can access the PIDs and data for the wheel-speed sensors, it is possible to observe play in the bearings as the car corners and brakes. Speeds may drop dramatically when compared to the inputs from the other wheels. If the ABS/ESC system detects this condition, it will disable the system and illuminate the ABS light. If a vehicle has these symptoms, replace the bearing or hub unit, even if it is not making noise or no play is present.





Automotive

Body Shop EV Repair



In 2024, Hertz decided to sell off many of its electric vehicles (EVs). One of the main reasons cited was that people kept crashing them. They also expressed concerns about the lack of collision shops willing to repair EVs and the lengthy period the vehicles would be out of service. But what was a problem for Hertz represents a significant opportunity for body shops.

Repairing the body and chassis of an EV is quite similar to making those repairs on internal combustion vehicles. You still have steel, plastic and paint that must be repaired or replaced. However, if the damage extends to the high-voltage battery or the drive unit, the repair process becomes a little more complex. The learning curve for working around high-voltage systems requires an investment in both training and specialized tools. Performing repairs without proper safety and high-voltage system training can be costly for your shop. In some cases, a 300-volt battery shorting out can cause more damage than just a fender bender. Having the appropriate tools and personal protective equipment is essential.

The first piece of equipment you’re going to need is a lift. If you want to have a flexible floor plan for your shop to help improve workflow, your body shop might want to utilize a portable lift to do wheel work, body repair or even detailing. But not all portable lifts are suitable for EVs. First, make sure it has sufficient rating for the lift capacity. Remember that most EVs are heavier than their internal combustion counterparts, thanks to the big battery pack underneath. Also, consider how they contact the vehicle when lifting. Frame-engaging scissor lifts typically have a wide lifting platform that extends far beneath the vehicle, potentially risking damage to the EV battery pack. BendPak has addressed these issues with QuickJack.

QuickJack is a line of portable lifts that are frame-engaging with an open center design, giving the operator the freedom to perform wheel, brake and suspension work, plus the convenience of under car access for collision repairs. The 600 ELX model was designed specifically for EV service with a rated lifting capacity of 6,000 lbs. and super long frames that offer the widest possible spread of lifting point access. When the job is done, QuickJack collapses to around three inches tall and can be hung on a wall or slide underneath the vehicle or even your toolbox. But for jobs where you need to remove the high-voltage battery pack or stand under the vehicle to work, you’re going to need a full-rise lift, most likely a two-post model.

In addition to having sufficient rated lifting capacity, you’ll need a lift with the ability to reach the OEM-recommended lift points on the vehicle you’re servicing. Tesla’s Model S, for example, has specific jack points that must be utilized at the outermost edge of the vehicle chassis. This minimizes the risk of battery damage and provides ample room beneath the chassis for battery pack removal. Arms that can’t reach these points can lead to costly damage to the battery pack. The BendPak AP series of two-post lifts such as the 10 AP are designed to handle the added weight and hard-to-reach lifting points of EVs. Their unique triple telescoping arms not only extend further, they also retract shorter than other arms to access enclosed pickup points. Plus, BendPak’s patented automatic arm restraints keep the arms where you put them. Even when handling a heavy EV, while a drive-on lift may seem like a good alternative, this design doesn’t allow for battery removal due to the obstruction caused by the runways.

The second piece of equipment that you’ll need is a battery lift to safely and ergonomically lower the battery pack from under the vehicle. With battery packs weighing up to 2,000 lbs. or more and costing thousands of dollars, you don’t want to trust a homemade solution. BendPak’s Mobi-EVS Battery-Powered Mobile EV Battery Lift Table slides under a two-post lift to control the descent of the battery and align the battery inside the vehicle should it need to be removed for body repairs. The Mobi-EVS can also assist with removing heavy drive components with the right adapters.

The third essential tool is a charger. The charger isn’t just a convenience; it serves as a diagnostic tool to determine whether the battery and charging system are functioning as they should. As mentioned earlier, you have to develop those “mind tools” by training and then also look at the service information.

For body repairs, it’s just as critical as CAT 3 insulated gloves and working on EVs. OEMs like Tesla and Rivian all have service information websites online for their all-electric lineups. These sites typically include the first responder guides and positioning statements, and they’re available free for you to use. You can also purchase a subscription for more detailed information with options ranging from 24 hours to up to a year. When reviewing service information and positioning statements, it quickly becomes apparent that many body repairs on EVs are very similar to those on conventional vehicles.

Still not convinced your body shop should be servicing EVs? Consider this: insurance analysts at LexisNexis found that EV owners’ frequency of insurance claims has increased by about 14.3% while the severity of the claim (or amounts paid out) has risen to 14.5%. This means that EVs are more likely to crash than internal combustion vehicles, and their repairs tend to be more expensive for body shop owners. These statistics should sound like a great business opportunity.

This video is sponsored by BendPak.





Automotive

Rotary Solutions Debuts R1250 Leverless Tire Changer at SEMA 2024



Rotary Solutions, part of Vehicle Service Group (VSG), a Dover company, has released the Rotary R1250 Leverless Tire Changer. This advanced, turnkey tire-changing solution improves shop efficiency and profitability by allowing automotive technicians a safer, faster and easier way to change tires safely. The R1250’s debut was a success at this year’s SEMA Show in Las Vegas, attracting professionals from across the industry.

Historically, tire changing has been a physically demanding task for technicians. As end-of-day and end-of-week fatigue sets in, lifting heavy tires on and off cumbersome machines can result in unsafe work conditions, inaccurate tire mounting and demounting, wheel damage, extended service times and unsatisfied customers. Rotary’s R1250 Leverless Tire Changer eliminates those risks with features designed for accuracy, speed and ease of use, requiring no heavy lifting or hand tools.

“With the R1250, changing tires has never been more efficient,” said Don Vanderheyden, vice president of business development for Rotary Solutions. “The R1250 provides automated options for several actions tire technicians perform regularly.”

Key features that set the R1250 apart include:

  • Pneumatic frontloading wheel lift for strain-free setup
  • Dual-bead rollers for faster mounting and demounting
  • Laser-guided, automatic tool positioning for perfect accuracy
  • Patented, quick-locking center-clamping pedestal that helps prevent accidental wheel damage
  • Telescoping, three-position pedestal to service a wide range of wheels
  • Built-in memory functionality and intuitive controls for easy operation

Additionally, the R1250 is ready to use right out of the box — no extra tools are required. With pushbutton controls and synchronized bead rollers, technicians can stay in virtually one spot, minimizing the risks of strain and injury.

“If you value time over sweat, the R1250 is the easiest Rotary tire changer to use for changing tires while improving your shop’s profits,” Vanderheyden said. “This turnkey system allows shops to change tires faster, with less labor, and at a higher quality — instantly boosting customer satisfaction and shop productivity.”

To watch a demonstration video of the R1250, click here.

For more information, click here.





Automotive

Take a closer look at the difference between various pools like HK, SDY, and SGP pools.

The world of situs toto HK, SDY, and SGP pools offers players a diverse range of experiences, each with its unique characteristics and appeal. Understanding the differences between these pools can help enthusiasts appreciate their nuances and find the one that best suits their preferences.

Hong Kong (HK) Pool

  1. Pace and Excitement: The HK pool is known for its fast-paced and dynamic draws, reflecting the vibrant and energetic culture of Hong Kong. The regularity and speed of draws keep players engaged and on their toes.
  2. Time Zone Appeal: Being based in Hong Kong, the draw times cater primarily to an Asian audience, though its global popularity ensures players from various time zones participate.
  3. Patterns and Trends: Many players enjoy analyzing HK pool results due to its structured patterns and high-frequency draws, making it a favorite for those who love spotting trends.
  4. Cultural Connection: HK pool carries a sense of tradition and prestige, as it has been a prominent part of the gaming culture in Hong Kong for decades.

Sydney (SDY) Pool

  1. Laid-back Atmosphere: SDY pool reflects the relaxed and friendly Australian spirit, offering an approachable and enjoyable experience for players.
  2. Draw Timings: The timings are particularly suitable for players in the Australian and Asia-Pacific region, but its appeal extends globally thanks to online accessibility.
  3. Casual Appeal: Players often find SDY pool to be less intense compared to other pools, making it ideal for those who want a more casual gaming experience.
  4. Community Interaction: SDY pool has a strong sense of community among its players, with many enjoying the camaraderie and shared excitement.

Singapore (SGP) Pool

  1. Structured and Reliable: SGP pool is renowned for its highly professional and organized approach, reflecting Singapore’s reputation for efficiency and precision.
  2. Global Reach: SGP pool has a vast international following, thanks to its fair practices and accessibility via online platforms.
  3. High Stakes and Thrill: Players are often drawn to the larger jackpots and competitive nature of SGP pool, adding an extra layer of excitement.
  4. Frequency and Predictability: With a predictable schedule, SGP pool makes it easy for players to plan their participation and enjoy the experience consistently.

Key Differences

FeatureHK PoolSDY PoolSGP Pool
AtmosphereHigh-energy, fast-pacedRelaxed, approachableStructured, competitive
PopularityAsia-focused, global reachRegional with growing global appealStrong international following
Draw FrequencyHighModerateModerate
Cultural NuanceTraditional and vibrantCasual and friendlyProfessional and organized
Player EngagementPattern analysis, quick drawsSocial and community-basedJackpot-driven excitement

Choosing the Right Pool

The choice between HK, SDY, and SGP pools ultimately depends on what kind of experience you’re looking for.

  • If you love high-energy games and frequent draws, HK pool might be your top choice.
  • For a laid-back and community-driven vibe, SDY pool is the way to go.
  • If you prefer a structured and high-stakes environment, SGP pool offers a professional and thrilling experience.

Each pool has its own charm, and exploring their differences adds to the excitement of participating in the world of toto and togel. Whether you stick to one or try them all, the journey is sure to be as rewarding as the games themselves!

Rotary Solutions Debuts R1250 Leverless Tire Changer at SEMA Show

Rotary Solutions, part of Vehicle Service Group (VSG), a Dover company, has released the Rotary R1250 Leverless Tire Changer. This advanced, turnkey tire-changing solution improves shop efficiency and profitability by allowing automotive technicians a safer, faster and easier way to change tires safely. The R1250’s debut was a success at this year’s SEMA Show in Las Vegas, attracting professionals from across the industry.

Historically, tire changing has been a physically demanding task for technicians. As end-of-day and end-of-week fatigue sets in, lifting heavy tires on and off cumbersome machines can result in unsafe work conditions, inaccurate tire mounting and demounting, wheel damage, extended service times and unsatisfied customers. Rotary’s R1250 Leverless Tire Changer eliminates those risks with features designed for accuracy, speed and ease of use, requiring no heavy lifting or hand tools.

“With the R1250, changing tires has never been more efficient,” said Don Vanderheyden, vice president of business development for Rotary Solutions. “The R1250 provides automated options for several actions tire technicians perform regularly.”

Key features that set the R1250 apart include:

  • Pneumatic frontloading wheel lift for strain-free setup
  • Dual-bead rollers for faster mounting and demounting
  • Laser-guided, automatic tool positioning for perfect accuracy
  • Patented, quick-locking center-clamping pedestal that helps prevent accidental wheel damage
  • Telescoping, three-position pedestal to service a wide range of wheels
  • Built-in memory functionality and intuitive controls for easy operation

Additionally, the R1250 is ready to use right out of the box — no extra tools are required. With pushbutton controls and synchronized bead rollers, technicians can stay in virtually one spot, minimizing the risks of strain and injury.

“If you value time over sweat, the R1250 is the easiest Rotary tire changer to use for changing tires while improving your shop’s profits,” Vanderheyden said. “This turnkey system allows shops to change tires faster, with less labor, and at a higher quality — instantly boosting customer satisfaction and shop productivity.”

To watch a demonstration video of the R1250, click here.

For more information, click here.





Automotive

Relay Diagnostics: Essential Tools Every Technician Needs

Explore the essential tools for diagnosing relays and circuits with Andrew Markel. From breakout devices to relay testers, learn how to save time, avoid false negatives, and make accurate diagnoses. Relays are more complex and expensive than you think—get the inside scoop!

This video is sponsored by Auto Value and Bumper to Bumper.

The post Relay Diagnostics: Essential Tools Every Technician Needs appeared first on Brake & Front End.



Automotive

EV Tire Repair Tips

EVs are not immune to tire punctures. Just like any tire repair, you’re going to want to begin by removing the tire from the wheel and doing a thorough inspection of the puncture or leak. Look for any signs that it was run underinflated for an extended period of time. 

With the rim removed from a tire that was on an EV, we can see that it has a foam core. Many EVs and hybrids use these types of tires to reduce tire noise. Mounting and balancing these tires is the same as any other tire. But, the one difference is how a puncture is repaired. 

For EV tires with this sound suppression foam, you’ll need to cut and remove a section of the foam to inspect the puncture from inside the tire. Once you’ve determined that the puncture is in an area that is safe to repair, you’ll need to take a closer look at the adhesive that was used to glue the foam in place.  

With the foam cut out, we can see remnants of the adhesive used to hold the foam to the inside of the tire. Cured adhesives will need to be completely removed prior to installing a patch or plug. To remove the adhesive, clean the area with a rubber cleaner and a scraper. Follow that up with your low-speed buffer to create a smooth even texture for maximum adhesion of the patch.   

Move on to the next steps of the proper tire repair process including, drilling out the injury with a carbide cutter and installing the repair using chemical vulcanizing cement. Always use the adhesive recommended by the manufacturer of the patch. 

With the repair securely in place, seal the area with inner liner sealer and the tire is ready to return to service. Reinstalling the foam is optional. If desired, you can use the inner liner sealer to prepare the area for reapplying the foam if the adhesive has lost its tack. 

Next, mount and balance the tire and rim. It is recommended that the service kit for the TPMS sensor is serviced whenever the tire is removed from the rim. With the rim back on the vehicle, we can make sure the TPMS light is out for the customer. 

This video is sponsored by BendPak.





Automotive