STRTR Relay Malfunction
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the STRTR relay.
- Ignition ON, transmission in Park/Neutral. Verify that a test lamp illuminates between the relay coil ground circuit terminal and B+.
- If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
- Probe the STRTR Relay switch B+ circuit terminal with a test lamp that is connected to ground. Verify that the test lamp illuminates.
- If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. Inspect the 175 A MEGA fuse for an open. If the circuit tests normal and the 175 A MEGA fuse is open, test the relay controlled output circuit for a short to ground.
- Connect a test lamp between the relay coil ground circuit terminal and the relay coil control circuit terminal.
- Ignition ON, transmission in Park/Neutral. Command the Starter Relay ON and OFF with a scan tool, or turn the ignition switch between the START and RUN positions. The test lamp should turn ON and OFF when changing between the commanded states.
- If the test lamp is always ON, test the relay coil control circuit for a short to voltage. If the circuit tests normal, replace the ECM.
- If the test lamp is always OFF, test the relay coil control circuit for a short to ground or and open/high resistance. Inspect the STRTR fuse for an open. If the STRTR fuse is open, test the relay controlled output circuit for a short to ground, or replace the starter solenoid (LMM) or starter. If the circuit and fuse test normal, replace the ECM.
- Connect the STRTR relay.
- Install a test lamp between the starter ring terminal S X2 and ground.
- Ignition ON, transmission in Park, command the Starter Relay ON with a scan tool, or turn the ignition switch to the START position. The test lamp should illuminate.
- If the test lamp does not illuminate, test the crank voltage circuit for an open/high resistance. If the circuit tests normal, test or replace the STRTR relay.
- If all circuits test normal, test or replace the starter solenoid (LMM 6.6L Diesel), or the starter (all other engines).
IMPORTANT:
The engine may begin to crank.