Fault Conditions

P1640
Main Relay Circuit. No Voltage to Control Module pin 1.

Fault symptoms
- Engine will not start.
- CHECK ENGINE.
- Misfiring may occur before trouble code is generated.

On-Board Diagnostics
Type of diagnosis:
- Continuous. But interrupted when fault criteria fulfilled and does not restart until next driving cycle.

Enable conditions:
- Crankshaft rotating.

Fault criteria:
- Main relay voltage below 5V for more than 1 S.

Dependents:
- None.

System reaction to a fault:
- None.

OK report:
- Enable criteria fulfilled and fault criteria not fulfilled within 60 S.

Fault handling: See "Fault diagnosis, general" for more information.
- Type III.

Diagnostic help
Fault diagnosis concerns electrical fault in connecting leads or in the relay.

Functions in the diagnostic tool related to the fault:
- Main relay voltage, unit V.

See also the description of readings in "Fault diagnosis, general" for more information.

Checking the wiring
Jiggle the wiring harness at several points and in different directions to detect intermittent breaks and short circuits. Observe the multimeter, diagnostic tool or test lamp during the check.

Proceed to Diagnostic Procedures Checking the Relay Power Supply