Ground Circuit Checks
- Check ground circuits to PCM for continuity to ground. See appropriate wiring diagram in the WIRING DIAGRAMS article to determine PCM ground terminals. Resistance to ground should be zero ohms. If reading is other than zero ohms, repair open circuit to ground.
- Using a voltmeter, touch negative lead to a good ground. Touch positive lead to each ground terminal. With vehicle running, voltmeter should indicate less than one volt. If reading is greater than one volt, check for open, corrosion, or loose connection on ground lead.