Function

ABS/EDL/ASR Bosch 5.3 On Board Diagnostic (OBD)
Function
The ABS control module is capable of On Board Diagnostic (OBD). The OBD concept relates only to the electrical and electronic parts of a system; in other words it only registers malfunctions which have an effect on the electric signals. Fundamentally, 19 different malfunction sources are distinguished.
The 26-pin ABS control module w/EDL -J104- forms a compact hydraulic control module with the hydraulic unit, as does the 31-pin ABS control module with EDL and ASR -J104-. The hydraulic control module is located on the lefthand side of the engine compartment. The control module is equipped with DTC memory. The connection for On Board Diagnostic (OBD) is located under the cover next to the handle on the parking brake lever.
If voltage supply falls below 10 volts, the ABS system shuts off. All relevant warning lamps light up. The system will switch itself back on though, once voltage supply rises above 10 volts again. The warning lamps will switch off. For complete loss of voltage, open circuit in a wire or fuse, only the ABS warning lamp lights up.

Note: Anti-Slip Regulation (ASR) is not installed to vehicles with 4 Motion (all-wheel-drive).

The control module recognizes malfunctions during vehicle operation and stores them in a DTC memory. This information is retained even if battery voltage fails.
Periodically occurring malfunctions are also recognized and stored as DTCs. If this malfunction does not occur again for 20 vehicle starts or one long trip, the DTC is erased from DTC memory.
After ignition is switched on or engine is started, the ABS warning light -K47-, the traction control indicator light -K86- (only for vehicles with ASR) and the red warning light for brake system -K118, light up for approximately 2 seconds.
Anti-Slip Regulation (ASR) is a vehicle safety system that prevents the wheels from slipping during acceleration. Depending on the control module coding, ASR is also able to perform an engine drag-torque regulation (MSR). MSR prevents the powered wheels from being blocked via an excessive engine braking, e.g. when downshifting. ASR works throughout the entire speed range. When ASR is in regulation mode, the ASR indicator lamp blinks 3 times per second.
The ABS control module -J104- installed in the vehicle is coded. New control modules for vehicles with ASR from the parts distribution center are uncoded and must be coded after being installed.
A test sequence (self-test) is performed in the control module during this time, with the following functions:
^ Supply voltage is tested (minimum 10.0 volts).
^ Control module and valve coils are checked
^ An electric test of the wheel speed sensors is performed; this test will not complete successfully unless vehicle is driven for 30 seconds at above 60 km/h.
^ The control module coding is being checked.