PSG16 / P0687 FD
Read the instructions below then
start the fault diagnostic procedure.
Symptom: Fault indicator lamp (for further information see WIS Fault diagnosis, general)
Engine shut off.
Engine does not start.
Main Relay Circuit. Voltage drops to late
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Fault symptom
Fault indicator lamp (for further information see WIS Fault diagnosis, general)
Engine shut off.
Engine does not start.
On-board diagnosis
Type of diagnosis:
Enable criteria:
Fault criteria:
Time difference between control module grounding of the relay and discontinued control module power supply is more than 2 seconds. |
System reaction to a fault:
OK report:
Fault criteria NOT fulfilled for 2 s. |
Checking the wiring harness
• | Faults in the control module female connector can be the cause of the DTC. Check the connector with respect to oxidation, depressed pins and pin clamping force. |
• | Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short-circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force. |
Diagnostic help
Counter is reset during each engine shut-off.
A poor contact or ground connection could cause the control module to experience a break in current.