E041

Code E041 - Cam Sensor Circuit Failure:

Wiring Diagram for Code E040 - Cam Sensor Circuit Failure:

CODE E041 - CAM SENSOR CIRCUIT FAILURE

Circuit Description:

For timing of spark plug firing a cam sensor "hall effect" switch is used. The sensor sends a signal (Sync-Pulse) to the ignition module when cylinder # 1 is 25° after top dead center on the compression stroke. This signal is used to start the correct sequence of coil firing, and to enable sequential fuel injection. The engine will continue to run if the cam signal from the cam sensor to the C3-I module is lost while running, however, will not restart after shut down. If the failure is in the cam signal output portion of the C3-I module (terminal "J") or the "SFI" cam signal CKT 630 to ECM terminal "A11", the ECM will switch to the simultaneous mode as long as the fault is present. In either failure mode a Code E041 will be stored.

Code E041 is set when the following conditions are met:

a. Engine is running
b. Cam sensor signal not received by ECM in last 1 second interval




Test Description: The following numbered steps correspond with the step numbers on the diagnostic chart.

1. Checks to see if ECM recognizes a problem, and sets Code E041. If the engine cranks, but will not start and a Code E041 was displayed, the fault is in the ignition system portion of the Cam Sensor circuit and should be diagnosed using Chart A-3, "Cranks But Will Not Run".

2. The voltage to ECM terminal "A11" is supplied by the ignition module. If voltage reading is below 6 volts, the fault is in CKT 630, a poor connection at the C3-I module, or faulty C3-I module.




Diagnostic Aids:

An intermittent may be caused by a poor connection, rubbed through wire insulation or a wire broken inside the insulation.

Check For:

a. Poor Connection or Damaged Harness - Inspect ECM harness connectors for backed out terminal "A11", improper mating, broken locks, improperly formed or damaged terminals, poor terminal to wire connection and damaged harness.

b. Intermittent Test - If connections and harness checks out ok, monitor A Digital Voltmeter connected from ECM terminal "A11" to ground while moving related connectors and wiring harness. If the failure is induced, the voltage reading will abruptly change. This will help to isolate the location of the malfunction.

c. Symptom Indicators

- If Cam Signal from Cam Sensor to C3-I module is lost while running, engine will not restart after shutdown.

- If Cam Signal output from the module or wiring etc., to the ECM has failed, engine will restart after shutdown.