Summary

TRACS

Summary






TRACS is an anti-wheel slip system integrated with the ABS system.

The system is mainly designed to assist with moving off on slippery surfaces at speeds up to approx. 40 km/h (25 mph). At speeds over 40 km/h (25 mph), TRACS has only a very limited effect.

Once the ignition is switched on, TRACS is engaged at all times. It can only be disengaged by pressing the switch.

If the control module detects via the front wheel sensors that one of the drive wheels is turning taster than the other, TRACS closes the inlet valve and the pump cuts in, pumping brake fluid to the slipping wheel's brake caliper. This builds up pressure in the brake circuit, and the brakes are applied just enough to ensure that engine power is divided between the drive wheels so that power is applied to the road via the drive wheel with the most grip. The process is independent of how much power the engine is putting out.

In cars with TRACS, the control module monitors continuously how much the brakes are being used and calculates the temperature in the front wheel brake discs. If TRACS is engaged and the estimated temperature becomes too high, approx. 450° C (842° F), TRACS is disabled and the TRACS warning light comes on. This prevents the brakes overheating. The light goes out once the estimated temperature has fallen below approx. 350° C (662° F) and TRACS is engaged again. However, the ABS system remains active the whole time. The control module retains data on the estimated brake disc temperature for as long as the control module 30-supply is connected.