Code 41, Cam Sensor CKT: Notes

Code 41 will set if engine is running and a cam sensor signal is not received by ECM for last 2-5 seconds.

1. Verifies proper operation of circuits No. 633, 644 and 645.
2. Tests cam signal circuit from C(3)I ignition module to ECM.
3. If harmonic balancer windows are interfacing with cam sensor, voltage reading may be zero. Bumping engine using starter will cause condition to go away.
4. If voltage reading is varying around a midpoint of 10.5 volts and connections are good, ECM is faulty.