Ground Circuits
- Using an ohmmeter, check for continuity to ground on appropriate ECU ground terminals. See POWER & GROUND CIRCUITS TERMINAL IDENTIFICATION table. See Figure. Resistance should be zero ohms for each circuit. If reading is not zero ohms, repair open to ground.
- Using a DVOM, touch negative lead of voltmeter to a good ground. Touch positive lead of voltmeter to each ground terminal. With vehicle running, voltmeter should indicate less than .1 volt. If voltmeter reading is greater than .1 volt, check for open, corrosion or loose connection on ground lead.