Diagnostic Trouble Codes (DTCS)

A diagnostic trouble code (DTC) is stored if the control module detects a fault.

Some malfunctions that have been detected repeatedly during several driving cycles may permanently turn off the functions adaptive cruise control, collision warning, RSIRoad Sign Information and brake assistance as well as store a diagnostic trouble code (DTC) for this.

A permanently switched off system can only be reactivated by resetting DTCs in the Forward Sensing Module (FSM), Central electronic module (CEM), Brake control module (BCM) in the same operating cycle.

A driving cycle includes ignition on and ignition off.

If a fault occurs in the functions for adaptive cruise control, brake support in the event of the collision risk, Lane Departure Warning (LKA), (Lane Keeping Aid) and Driver Alert Control (DAC) functions, a fault counter counts up per function. If these counters, regardless of each other, reach a predetermined value below one and the same operating cycle, independent error flags are set in the monitoring logistics in the Central electronic module (CEM).

Permanent switching off of the functions results in diagnostic trouble codes (DTCs) being stored in the Forward Sensing Module (FSM), Brake control module (BCM), and in the Central electronic module (CEM). The diagnostic trouble codes (DTCs) must be erased from all control modules during an operating cycle to reset these error flags.