Circuit/System Testing
WARNING: This page is about a different car, the 2012 GMC Yukon, 2012 Chevrolet Tahoe, and 2012 Cadillac Escalade. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the high voltage circuit impact detector sensor.
- Ignition OFF and scan tool disconnected, open and close the driver door, and wait 1 minute. Test for less than 5 Ω between the low reference circuit terminal 2 and ground.
- If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the serial data gateway module.
- Connect a DMM, set on a manual setting that can read 12 V with the MIN/MAX function enabled, between the signal circuit terminal 1 and ground.
- Ignition ON, wait 10 seconds, The DMM reading should be less than 1.0 V.
- If greater than the specified range, test the circuit for a short to voltage. If the circuit tests normal, replace the serial data gateway module.
- Verify the DMM MAX reading is greater than 6.0 V.
- 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 serial data gateway module.
- If all circuits test normal, test or replace the high voltage circuit impact detector sensor.
NOTE:
The serial data gateway module will attempt to communicate with the high voltage circuit impact detector sensor for 5 seconds immediately after the ignition is turned ON. After 5 seconds the signal circuit will be inactive.
NOTE:
The DMM should not be set on the Auto Range scale. The Auto Range will give erratic test results.