On Board Diagnostic (OBD) function: Notes
The On Board Diagnostic (OBD) function of the ESP can detect a total of 41 different malfunctions.
NOTE:
If a malfunction is detected by the On Board Diagnostic (OBD) function, the system concerned switches itself off automatically for the duration of the current driving cycle. This is indicated by the relevant warning light in the instrument cluster. For further details refer to the section on WARNING LIGHT FUNCTIONS
and WARNING LIGHT FUNCTIONS TABLE
.
WARNING:
If you drive the vehicle after a malfunction has been detected by the On Board Diagnostic (OBD), bear in mind that the function of the brake system is now restricted. If the brake system warning symbol comes on, this means the brake pressure at the rear wheels is no longer controlled by the electronic brake force distribution function and the rear wheels can lock up even under light braking. The excessive braking at the rear wheels can cause the tail of the vehicle to break loose unexpectedly, which can result in an accident
NOTE:
The above does not apply to the DTC "01119 Gear recognition signal". See DIAGNOSTIC TROUBLE CODE (DTC) TABLE; DTC'S 00000 TO 00526
. If this malfunction is detected, none of the warning lights will come on. This malfunction affects the system's ability to recognize whether a forward or reverse gear is engaged; it can be compensated by ABS control module (w/EDL) -J104- via plausibility criteria.
The various control functions are inactive when VAS 5051 vehicle diagnostic, testing and information system or VAG 1551 scan tool is connected and communication has been established with ABS control module (w/EDL) -J104-. The ABS warning light -K47-, the traction control indicator light -K86- and the brake system warning symbol will come on.
The system performs a self-test routine when the ignition is switched on before every trip. This process is indicated by the yellow ABS warning light -K47- and the traction control indicator light -K86-. The warning lights will go out after about 3 seconds. The self-test routine continues for a short time when the vehicle is moving, as some malfunctions can only be detected above a certain speed.
During the self-test process there will be audible noise from the valves and relays and from the return flow pump and the priming pump in the hydraulic unit. There will also be a slight pulsation at the brake pedal (usually at about 6 km/h).
NOTE:
This is unavoidable, and is not a malfunction which requires repair.