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Voltage Signal: Testing and Inspection

Back - Up And Voltage Signal Circuit:





To test the battery back-up and Voltage signal, proceed as follows:

1. Using a Volt meter, check the Voltage between ECU harness terminal 103 and ground.

Voltage: System Voltage

2. Disconnect the negative battery cable and the ECU connector.
3. Using an Ohm meter, check for continuity between the positive battery terminal and ECU harness terminal 103.

Continuity Should exist

4. Using an Ohm meter, check for continuity between chassis ground (not the negative battery terminal) and ECU harness terminal 103.

Continuity: should not exist

If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed, confirm that the repair has corrected the problem.

If the trouble returns, it is possible that there is an intermittent failure of the component or the ECU. Check for looseness at all harness junctions and test for an intermittent failure.