Circuit/System Testing
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WARNING:
Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.
The High Voltage Disabling procedure will perform the following tasks:
Failure to follow the procedures exactly as written may result in serious injury or death.
The High Voltage Disabling procedure will perform the following tasks:
- Identify how to disable high voltage.
- Identify how to test for the presence of high voltage.
- Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.
- Perform the High Voltage Disabling procedure.
- Reconnect the 12-volt battery.
- Ignition OFF, disconnect harness connector X1 of the BECM and the PIM.
- Ignition ON, verify that a test lamp illuminates between the wake up signal circuit of the PIM and ground, and the BECM and ground as follows:
- PIM X1 19
- BECM X1 12
- If the test lamp does not illuminate, test the circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the SDGM.
- Ignition OFF, verify that a test lamp does not illuminate between the PIM wake up signal circuit terminal 19 and ground.
- If the test lamp illuminates, test the circuit for a short to voltage. If the circuit tests normal, replace the SDGM.
- If all circuits test normal, replace the SDGM.