DME Main Relay

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TEST PROCEDURE:

Status Monitoring:
With ignition "ON" or during engine operation, the main relay is activated with ground potential at terminal 85 (display: ON). The relay switches on and supplies the Digital Motor Electronic (DME), Electronic Transmission Control (EGS), Electronic Throttle Control (EML) and Anti-Lock Brake (ABS) control units with voltage.

Possible Defect Causes:
- Wire to DME control unit Pin 27 defective
- DME relay or voltage supply not OK.
- Voltage supply for DME control unit not OK.
- The control unit is defective if no ground potential is output at control unit Pin 27 (display: Off) although the above points are OK.