Ground Circuit Checks
- Using an ohmmeter, check ground circuits to ECM for continuity to ground. See appropriate wiring diagram in WIRING DIAGRAMS article in this section to determine ECM ground terminals. Resistance to ground should be zero ohms. If reading is other than zero ohms, repair open circuit to ground.
- Using a DVOM, touch negative voltmeter lead to a good ground. Touch positive voltmeter lead 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, corrosion or loose connection on ground lead.