Traction Control System TPS

GENERAL
All V6 engine models are equipped with the Traction Control System (TCS). The TCS control module distributes a throttle position signal containing information on the opening angle of the TCS throttle.

Under normal conditions the two throttles (main throttle and TCS throttle) operate synchronously, that is to say they both have the same angle. If the TCS is activated the opening angle of the TCS throttle will be reduced, resulting in asynchronous operation of the two throttles. When the systems is activates, the TCS throttle is the one that specifies the actual opening angle and the transmission control module receives the throttle position signal from the TCS in order to control gear shifting performance.

The function ceases when:
- No throttle position signal is received from the TCS
- The TCS ACTIVE signal is absent
- Limp-home mode is activated





TCS ACTIVE
The Traction Control System identifies wheel spin and reduces engine torque by controlling the TCS throttle. The TCS indicator lamp in the main instrument display panel lights up at the same time. This is because the TCS control module grounds pin 12. Pin 4 of the transmission control module is also grounded simultaneously.

The transmission control module thus receives wheel spin information via the voltage levels (B+ circuit or ground).

The result is that gear shifting performance is regulated as a function of the TCS throttle's opening angle, the TCS throttle position signal, instead of the main throttle's position signal from the Motronic engine control module. The gear shifting points are still determined by the position of the main throttle, however.

Furthermore, the indicator lamp comes on for 3 seconds when the ignition switch is turned to the ON position.