VPWR3 Check Power to PCM Relay

- Key OFF.

- Remove the PCM (ENGINE CONT.) relay.

- Key ON.

- Measure the voltage between the PWR wires at the PCM relay and ground.

- Are the voltages greater than 10 volts?

YES -- GO to VPWR4. VPWR4 Check Ground at PCM Relay

NO -- CHECK the 25A ENGINE CONT. fuse.
If OK, SERVICE the PWR wire(s) in question.