Circuit/System Testing
- Ignition OFF, disconnect the harness connector X2 at the SDG module.
- Ignition OFF and the scan tool disconnected, open and close the driver door, and wait 1 minute.
- Test for less than 5.0 ohms between the ground circuit terminal 18 X2 and ground.
- If greater than the specified range, test the circuit for an open/high resistance.
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal 8 X2 and ground.
- If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance.
- Test for 10.5-12.5 volts between the serial data communication enable circuit terminal 16 X2 and ground.
- If less than the specified range, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the applicable communication/control module.
- Ignition OFF, connect the harness connector X2 to the SDG module.
- Ignition OFF, disconnect the harness connector X1 at the SDG module.
- Ignition ON, test for 2.1-2.5 volts between the high speed GMLAN serial data bus low circuit terminal listed below and ground:
- Terminal 15 X1
- Terminal 16 X1
- If greater than the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the applicable communication/control module.
- If less than the specified range, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the applicable communication/control module.
- If all circuits test normal, replace the SDG module.
IMPORTANT:
The scan tool must be disconnected and the ignition switch OFF for 30 seconds for proper test results.