Ground Circuit Checks
- Using an ohmmeter, check ground circuits to PCM for continuity to ground. See appropriate wiring diagram in WIRING DIAGRAMS article to determine PCM ground terminals. If continuity does not exist, 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 voltage reading is more than one volt, check for open circuit, corrosion, or loose connection on ground lead.