P1312 - Combustion Detection Cyl 1+2

Combustion Detection Cyl. 1+2. Open Circuit / Short to B+.


Attachment 7050

Fault symptoms
• CHECK ENGINE.

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

Enable criteria:
- General conditions for this trouble code: Atmospheric pressure must exceed 72 kPa and the engine coolant and intake air temperatures must exceed -7°C.

- Engine running. Main relay voltage exceeding 10V. Ignition synchronized.

Fault criteria:
- Voltage exceeding 5V continuously during 200 combustions.

Dependents:
- None.

System reaction to a fault:
- None.

OK report:
- Enable criteria fulfilled. Fault criteria for P1312 or P1334 not fulfilled within 300 combustions.

Fault handling: (See section Fault handling III, other emission-related components and functions for more information.)
- Type III.

Diagnostic help
Fault diagnosis concerns an electrical fault in the connecting leads.
• Combustion Detection Cyl 1+2/Bank1, unit %

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.