Ground Circuits
- Using ohmmeter, check for continuity to ground at PCM ground terminals. See POWERTRAIN CONTROL MODULE CONNECTOR TERMINAL IDENTIFICATION . See Figure and Figure. Resistance should be zero ohms. If resistance is not zero ohms, repair open in ground circuit.
- Connect negative lead of voltmeter to a known-good ground. Backprobe positive lead of voltmeter to each PCM ground terminal. With vehicle running, voltmeter should indicate less than one volt. If voltmeter reading is greater than one volt, check for open, short to voltage, corrosion or loose connection in ground circuit.