2010 Cadillac CTS Sedan AWD V6-3.6L Page 572
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
Command the rear doors to LOCK and UNLOCK with the scan tool, the rear doors should perform the LOCK and UNLOCK function.
If B3130 00 is current, refer to UNLCK Relay Control Circuit Malfunction.
If B3135 00 is current, refer to LCK Relay Control Circuit Malfunction
Circuit/System Testing
UNLCK Relay Control Circuit Malfunction
1. Ignition OFF, disconnect the UNLCK relay.
2. Connect a test lamp between the control circuit terminal 85 and the B+ circuit terminal 86.
3. Command the rear doors to UNLOCK with a scan tool. The test lamp should briefly illuminate when commanding the UNLOCK state.
瀚慖f the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace
the BCM.
瀚慖f the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.
4. If all circuits test normal, test or replace the UNLCK relay.
LCK Relay Control Circuit Malfunction
1. Ignition OFF, disconnect the LCK relay.
2. Connect a test lamp between the control circuit terminal 85 and the ground circuit terminal 86.
3. Command the rear doors to LOCK with a scan tool. The test lamp should briefly illuminate when commanding the LOCK state.
瀚慖f the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace
the BCM.
瀚慖f the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
4. If all circuits test normal, test or replace the LCK relay.
Component Testing
Relay Test
1. Ignition OFF, disconnect the appropriate relay.
2. Test for 60-200 ohms between terminals 85 and 86.
瀚慖f not within the specified range, replace the relay.
3. Test for infinite resistance between the following terminals:
* 30 and 86
* 30 and 87
* 30 and 85
* 85 and 87
瀚慖f less than the specified value, replace the relay.
4. Test for less than 2 ohms between terminals 30 and 87A.
瀚慖f greater than the specified range, replace the relay.
5. Install a 3A fused jumper wire between the relay terminal 85 and 12V. Install a jumper wire between relay terminal 86 and ground. Test for
less than 2 ohms between terminals 30 and 87.
瀚慖f greater than specified range, replace the relay.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Relay Replacement (Attached to Wire Harness) (See: Power and Ground Distribution/Power Distribution Relay/Service and Repair/Relay
Replacement (Attached to Wire Harness))Relay Replacement (Within an Electrical Center) (See: Power and Ground Distribution/Power
Distribution Relay/Service and Repair/Relay Replacement (Within an Electrical Center))
