Code 42 (MFI CALIF. & New YORK) - Camshaft Position Sensor Circuit, No Signal For 3 Seconds: Notes

When distributor shaft rotates, a fluctuating magnetic field is generated due to changes in air gap between Camshaft Position (CMP) sensor and distributor shaft signal rotor. As a result, a reference voltage is induced in CMP sensor. This reference voltage is monitored by ECM to determine the crank angle input. ECM uses crank angle input to determine when to ground igniter, controlling ignition coil and ignition timing. Code 42 will set when CMP sensor signal input is not present at ECM for 3 seconds.

1. Checks for open, short to ground, or short to voltage in White wire between ECM and distributor, or a faulty ECM.
2. Checks for open in Blue/Black wire between main relay and distributor.
3. Checks for open in Black wire between distributor and G110.
4. Checks for a faulty CMP sensor.