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ECM Ground Circuit

  1. Using an ohmmeter, check for continuity to ground on ECM terminal A12 (Black/White wire). Ground for ECM is located behind right side of instrument panel. Resistance should be zero ohms. If resistance is not zero ohms, repair open in ground circuit.
  2. Using a DVOM, touch negative lead of voltmeter to a 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 wire.