DTC P0342/P0343 - CMP Sensor Circuit Malfunction
- P0342 - CMP Sensor Circuit Low Input
- P0343 - CMP Sensor Circuit High Input
- Install scan tool. Start engine and check if DTC P0342 or P0343 is present. If DTC is present, go to next step. If DTC is not present, problem is intermittent.
- Turn ignition off. Disconnect CMP sensor harness connector. Turn ignition on. Using a DVOM, check voltage between sensor harness connector terminal No. 3 and ground. See appropriate wiring diagram in WIRING DIAGRAMS section. Battery voltage should be present. If battery voltage is present, go to next step. If battery voltage is not present, check circuit between terminal No. 3 and SFI relay.
- Turn ignition off. Check continuity between CMP sensor harness connector terminal No. 1 and ground. If continuity is present, go to next step. If continuity is not present, check for open in circuit between terminal No. 1 and ground.
- Disconnect ECM harness connector. Check for continuity between ECM harness connector terminal No. 44 and CMP sensor harness connector terminal No. 2. If continuity is present, go to next step. If continuity is not present, check circuit between CMP sensor and ECM.
- Reconnect CMP sensor and ECM harness connectors. Using DVOM connected to ground, backprobe ECM harness connector terminal No. 44 or CMP harness connector terminal No. 2. Start engine. Voltage at 800 RPM and 3000 RPM should be zero and 5 volts. If voltage reading is not as specified, clean or replace CMP sensor. If voltage reading is as specified, go to next step.
- Check timing. Timing should be 4-14 degrees BTDC @ 800 RPM. If timing is not as specified, check if dowel pin on camshaft end is locked. Lock or replace dowel pin. If timing is as specified, clear DTC. See CLEARING DTC(S) . Retest system. If DTC resets, replace ECM.