Engine Control Module: Service Precautions

Permanent positive at the control unit
As the DME 2.10.1. includes a number of adaptive (self-learning) systems (oxygen sensor closed loop control, charge control, knock regulation), terminal 18 on the DME plug is supplied with a permanent positive voltage. If the plug is disconnected from the control unit or the battery, the engine has to be run to operating temperature and left running for approx. 10 mins. after the next starting sequence to enable the control unit to readapt itself.

The control unit contains a volatile fault memory, i.e. all the faults stored in the memory are erased once the control unit has been disconnected from the permanent positive voltage.