Electronic stability control uses sensors on each wheel and antilock brakes to monitor steering wheel angle and vehicle rotation. When it detects the vehicle may lose control, it automatically brakes wheels as needed and may reduce engine power to help the driver maintain stability, especially during hard turns or on slippery roads. Many vehicle manufacturers have their own names for electronic stability control systems, which will be required in all new vehicles by 2012. Using a scan tool during an alignment allows technicians to reset stability sensors and retrieve any trouble codes.

1. Electronic Stability Control Electronic stability control: Uses the speed sensors on each wheel and the ability to brake individual wheels…antilock brakes. ESC adds a control unit that monitors steering wheel angle and vehicle rotation around the vehicle's vertical axis. This unit uses the steering and rotation information to detect that the vehicle is about to travel in a direction different from the one indicated by the steering wheel position. Then ESC automatically brakes the appropriate wheel to help the driver maintain control. In many cases engine power also is reduced. How ESC helps drivers maintain control: A driver loses control when the vehicle goes in a direction different from the one indicated by the position of the steering wheel. This typically occurs when a driver tries to turn very hard (swerve) or to turn on a slippery road. Then the vehicle may understeer or oversteer. Steering Angle Sensor or Yaw Sensor

2. Electronic Stability Control Systems Audi: Electronic Stability Program (ESP). BMW: Dynamic Stability Control (DSC). DaimlerChrysler: Electronic Stability Program (ESP). Ford Motor Company: Advance Trac. General Motors: Active Handling System (Corvette), Stabilitrak (Pontiac, Buick, Cadillac). Jaguar: Dynamic Stability Control (DSM). Lexus: Vehicle Skid Control (VSC) Porsche: Porsche Stability Management (PSM). Toyota: Vehicle Skid Control (VSC) Volkswagen: Electronic Stability Program (ESP). Volvo: Dynamic Stability Traction Control (DTSC).

3. A Primer on Electronic Stability Control Systems and effects on wheel alignment services Snap-on Equipment Jack D. Michaels Training Center Conway Arkansas Wednesday, April 22, 2009 Ron Racine Technical Training Specialist

4. Compliance Date The compliance date for vehicle manufacturers consist of a phase-in starting September 1, 2008: “ All new light vehicles must be equipped with an ESC system that meets the requirements of the standard by September 1, 2012.” Page 3 of the FMVSS 126. Currently vehicle manufacturers equipped about 26% of model year 2006 light vehicles sold in the US with ESC. An increase to 71% is expected by model year 2011 with 100% ESC equipped vehicles by model year 2012. This applies to roadworthy vehicles with a gross weight rating of 4,536 kg (10,000 lbs) or less.

5. After the car is selected the aligner software will retrieve the instructions from the specification database and present this information to the technician.

8. On the reading screens an information icon (Solus Scanner picture) will appear to alert the technician that special functions exist that are recommended to be performed after the alignment. If the technician clicks on this icon then the information screens will be shown.

10. Using the Snap-on scan-tool to reset and calibrate SWAS This is an example of a 2008 Toyota Highlander having it’s SWAS sensor calibrated using a Snap-on Solus with 9.2 software The operation is simple: Steer straight ahead and Press “Y” on the Solus

11. Existing customers can use their Snap-on scanner in conjunction with the alignment machines to reset SWAS Using the scanner in conjunction with the aligner eliminates the need to drive the vehicle on a flat surface to find straight ahead Alignment technicians can use the wheel alignment machine to steer straight ahead and the scanner to reset the various sensors Using the Snap-on scanner allows the undercar technician to retrieve ESC and EPS trouble codes whenever present and access valuable industry based repair information The John Bean alignment software will have some provisions to guide the technician through the SWAS reset using a Snap-on Scanner Conclusion

12. Software Availability May aligner software release 161 vehicles are covered in the data base 9.2 Solus, Modis & Verus software release