Fault Conditions

P1670

Limp-home Relay, Open Circuit Or Short To Ground







NOTE: The relay/electrical circuit that activates the throttle's limp-home function is faulty.

Fault symptoms
- CHECK ENGINE.
- Cruise control inoperative.
- Throttle control may go into mechanical limp-home mode. P1251, P1260 or P1263 could be generated as a secondary fault.
- Starting problems, especially when engine is cold.

On-Board Diagnostics

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

Enable criteria:
- Engine running. Main relay voltage exceeding 10 V. Output not active.

Fault criteria:
- Output voltage below 2 V for more than 1 s.

Dependents:
- None.

System reaction to a fault:
- Cruise control is blocked.

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

Fault handling: (For more information refer to "Fault diagnosis, general". Fault Handling III, Other Emission-Related Components and Function)

- Type III.

Diagnostic help
Fault diagnosis concerns electrical faults in connecting cables or in the relay.

Check the wiring
Jiggle the leads and in-line connectors at various points and in different directions to detect any intermittent breaks or short circuits in the wiring. Observe the multimeter, test lamp or diagnostic tool while doing this.