BMW ABS and Traction Control Warning Lights (ASC, ASC+T, DSC), Transmission Not Shifting, E38, E39, X5
This answer is applicable for many BMWs in addition to the one listed below.
car year: 1997
car model: 528i
Why does the ABS & traction control lights @ dash come on? Is there a wheel speed sensor @ the front and back? Or just @ the back? Also automatic transmission doesn’t shift.
The E39 5-series (528i, 525i, 530i, 540i, M5 97-03), E38 7-series (740i, 740il, 750il 95-01) and the E53 X5 (3.0i, 4.4i, 4.6is, 4.8is 00-06) all use a similar ABS and Traction Control system. There are wheel speed sensors at all four wheels and the speedometer is fed vehicle speed info from one of the rear wheel speed sensors (left or right varies by chassis model). When the ABS and Traction Control lights are on at the same time, this is typically an indication that there is a fault in the ABS control unit. With this noted, a reading of the internal fault codes is in order prior to replacing any parts. The transmission is in a fail-safe mode if it is not shifting. This often happens when the ABS and/or traction control systems have faults, but not always. There could be a transmission fault at the core of the current issues. As with the ABS and traction control, the internal faults need to be checked.
The common engine management OBD-II readers will not read the ABS and/or traction control faults. The diagnostic will need to be done by a shop that has the appropriate diagnostic and coding tool, specifically for the BMWs.
Once we have fault information, we can consider the appropriate steps in repairing the issue. Just give us a call at 800-535-2002. More information on these systems can be found in the applicable Bentley repair manual.
Bentley repair manuals: