Ground Circuit Checks
- Using an ohmmeter, check ground circuits to Powertrain Control Module (PCM) for continuity to ground. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS to determine PCM ground terminals. See PCM LOCATIONS table. If continuity is not present, 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.