Lucerne V6-3.8L VIN 2 (2006)
-> Circuit Testing See: Testing and Inspection/Component Tests and General Diagnostics
-> Connector Repairs See: Testing and Inspection/Component Tests and General Diagnostics
-> Testing for Intermittent Conditions and Poor Connections See: Testing and Inspection/Component Tests and General Diagnostics
-> Wiring Repairs See: Testing and Inspection/Component Tests and General Diagnostics
Circuit/System Testing
1. Test for less than 1.0 ohm of resistance between the DLC ground circuit terminal 5 and ground.
-> If greater than 1.0 ohm, test the ground circuit for open/high resistance.
2. Ignition OFF, disconnect the harness connector (splice pack comb) at SP 300.
3. Ignition ON, with a scan tool, attempt to communicate with the instrument panel cluster (IPC). Communication should be available.
-> If no communication, disconnect the modules still connected to the DLC one at a time, starting with the furthest from the DLC and attempt to
communicate after each disconnect. When communication occurs, test the serial data circuit for a short to ground and a short to voltage
between the last module disconnected and the previous module disconnected. If the circuit tests normal, replace the last module disconnected.
If no communication is possible, test the serial data circuit for a short to ground, a short to voltage or an open/high resistance between the last
module disconnected and the DLC. If the circuit tests normal, replace the last module disconnected.
4. Install a 3-amp fused jumper wire to pin L of SP 300, harness side.
5. With IPC communications established, use the other end of the jumper wire to connect all other pins, harness side, one at a time and verify that
low speed communication remains available to the IPC.
Important: Allow communications for 5 seconds after connecting a module with the jumper to determine if communication is interrupted or not.
-> If low speed communication is interrupted after connecting an individual module at SP 300, test the serial data circuit between SP 300 and the
last module connected for a short to ground and short to voltage. If the circuit tests normal, replace the module that caused no communication.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
-> Control Module References for module replacement, setup, and programming. See: Testing and Inspection/Programming and Relearning
-> GMLAN Wiring Repairs See: Testing and Inspection/Component Tests and General Diagnostics