Ground Circuits

Disconnect PCM connectors. Using an ohmmeter, check for continuity to ground on PCM harness ground terminals. See PCM GROUND CIRCUIT TERMINALS . Resistance should be zero ohms. If not, locate and repair open in wire.
Reconnect PCM connectors. Using a voltmeter, connect negative lead of voltmeter to a good ground. Backprobe positive lead of voltmeter to each ground terminal. With vehicle running, voltmeter should indicate less than one volt. If voltmeter reading is greater than one volt, check for open, short, corrosion or loose connection on ground circuit. Repair as necessary.

PCM GROUND CIRCUIT TERMINALS