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.
- Ignition OFF, disconnect harness connector X1 of the BECM.
- Reconnect the 12-volt battery.
- Ignition OFF and scan tool disconnected, test for less than 1 volt between wake up signal terminal 13 and ground.
- If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.