1999 Lexus SC400 Traction Control Switch Replacement Cost

Traction control is a system that works in conjunction with the anti lock brake system and engine management system. As it sounds, traction control creates safer driving environment by preventing wheel spin due to over acceleration or high lateral acceleration. More advanced traction control systems will incorporate components of the transfer case and differential(s) to assist in directing power to the appropriate wheels when needed. Many vehicles have a switch to turn off the traction control system, which allows for difficult maneuvering of the vehicle in situations where traction control may limit the vehicle's abilities.

The traction control system uses the anti lock brake control module to access the wheel speed sensors. When the ABS control module notes that the wheels are moving at different speeds, or that one or more wheels are turning while the others are not, the traction control system will use the anti lock brake system actuator to slow the wheels without traction, and release the wheels that are sliding. Further, most traction control systems will access the engine control module to decrease engine power to prevent further wheel slip or skidding. Advanced systems will use the transfer case and differentials to transfer power to the front or back of the vehicle or to the tires with the most traction. When the traction control switch is deactivated, these functions are either not performed, or are performed to a much lesser degree. In many cases, this may also disable the anti lock braking system (ABS).

Since the traction control system is thoroughly integrated into the ABS system, any malfunction of the traction control system will cause both the traction control system and the anti lock braking system to be disabled. However, the traction control switch failing may cause no symptoms at all. In the event that traction control needs to be disabled, the switch would simply not function. This would leave the traction control and anti lock braking systems active. This is generally the case, but note that if the traction control system is disabled for any other reason, the vehicle may need to be turned off and restarted to enable the traction control system when the switch is not functioning.