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Ground Circuits

  1. Using an ohmmeter, check for continuity to ground on ECU ground terminals. Refer to the ECU GROUND CIRCUITS  table. Also, see Figure and Figure . Resistance should be zero ohms. If not, repair open ground circuit.
  2. Using a DVOM, touch negative lead of voltmeter to a good ground. See Figure or Figure . Touch positive lead of voltmeter to each ground terminal. See ECU GROUND CIRCUITS  table. With vehicle running, voltmeter reading should be less than .1 volt. If voltmeter reading is greater than .1 volt, check for open, corrosion or loose connection on ground lead.
ECU GROUND CIRCUITS

Application ECU Terminals
2.5L No. 1, 2 & 10