P1917
P1917NOTE: In naturally aspirated V8 engines, the relay for the additional water pump is only activated by the air-conditioning control module.
Additional Water Pump Relay Output Stage - Open Circuit
Diagnostic conditions
- Battery voltage between 10 V and 16 V
- Time after the engine is started longer than 10 seconds
Possible cause of fault
- Open circuit in voltage supply for triggering additional water pump relay
- Open circuit in triggering wire for additional water pump relay
- Fuse FE12 faulty (fuse carrier in E-box, radiator tank)
- Additional water pump relay faulty (resistance too high)
- DME control module faulty
Affected pins
DME control module connector A, pin 48, and additional water pump relay connector, pin 2
Diagnosis/troubleshooting
NOTE: If connector A is disconnected from the DME control module and the ignition is or was switched on, the 'DME Control Module TIMEOUT' fault is recorded in many control modules.
NOTE: If control module connector A was disconnected from the DME in the course of troubleshooting or if the voltage supply was interrupted elsewhere (battery, fuse), the throttle adjusting unit must be adapted.
