Circuit/System Testing

WARNING: This page is about a different car, the 2008 Cadillac DTS. However, it is still accessible from the selected car via links, so may be relevant.

Ignition OFF, disconnect the harness connectors X1, X2, and X3 of the CCSM.
Test for less than 1 ohm of resistance between the module ground circuit terminal M X1 and ground.
- If greater than 1 ohm, repair the ground circuit for an open/high resistance.
Ignition ON, verify that a test lamp illuminates between battery positive voltage circuit terminal E X1 and ground.
- If the test lamp does not illuminate, repair the battery positive voltage circuit for a short to ground or an open/high resistance. If the circuit fuse is open, also test the positive voltage outputs of the module for a short to ground. If the circuits test normal, replace the CCSM.
Ignition ON, verify that a test lamp illuminates between ignition voltage circuit terminal 1 X2 and ground.
- If the test lamp does not illuminate, repair the ignition voltage circuit for a short to ground or an open/high resistance. If the circuit fuse is open, also test the positive voltage outputs of the module for a short to ground. If the circuits test normal, replace the CCSM.
Test for infinite resistance between the data link connector (DLC) keyword 2000 serial data circuit terminal 7 and ground.
- If less than the specified value, test the serial data circuit for a short to ground.
Test for less than 1 volt between the DLC keyword 2000 serial data circuit terminal 7 and ground.
- If greater than the specified range, test the serial data circuit for a short to voltage.
Test for less than 1 ohm of resistance in the keyword 2000 serial data circuit between the CCSM terminal 9 X3 and the DLC terminal 7.
- If greater than the specified range, test the serial data circuit for open/high resistance.
If all circuits test normal, replace CCSM.