Diagnostic Procedure
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- If SIR diagnostic system check has been performed, go to next step. If SIR diagnostic system check has not been performed, go to SIR DIAGNOSTIC SYSTEM CHECK .
- Turn ignition off. Disconnect PPS ECU connector. See Figure. If PPS ECU connector shows signs of corrosion or damage, replace connector. See WIRE REPAIR . Go to step 10. If connector is okay, go to next step.
- Disconnect inside rear view mirror connector, located at rear of mirror assembly. If mirror connector shows signs of damage or corrosion, replace connector. See WIRE REPAIR . Go to step 10. If mirror connector is okay, go to next step.NOTE: Use Digital Multimeter (J-39200) and Connector Test Adapter Kit (J-35616-A) or Flat WIre Probe Adapter Kit (J-42675) when performing electrical tests.
- Turn ignition off. Inspect Yellow wire between mirror connector terminal No. 13 and SIR fuse for a short to ground, an open or high resistance. If a short to ground, an open or high resistance is found in circuit 1139 and corrected, go to step 10. If a short to ground, an open or high resistance is not found and corrected, go to next step.
- Inspect Dark Green wire between mirror connector terminal No. 4 and PPS ECU connector terminal "M" for a short to ground, an open or high resistance. See Figure. If a short to ground, an open or high resistance is found in circuit 2308 and corrected, go to step 10. If a short to ground, an open or high resistance is not found and corrected, go to next step.
- Inspect Dark Blue wire between mirror connector terminal No. 3 and PPS module connector terminal "L" for a short to ground, an open or high resistance. If a short to ground, an open or high resistance is found in circuit 2307 and corrected, go to step 10. If a short to ground, an open or high resistance is not found and corrected, go to next step.
- Turn ignition off. Connect a test light between ignition voltage circuit 1139 and PPS OFF air bag indicator circuit 2308. Ensure passenger seat is empty. Turn ignition on. If test light illuminates, go to next step. If test light does not illuminate, go to step 9.
- Replace rear view mirror. See REAR VIEW MIRROR under REMOVAL & INSTALLATION. Go to step 10.
- Replace PPS. See PASSENGER PRESENCE SYSTEM (PPS) under REMOVAL & INSTALLATION. Go to next step.
- Reconnect all PPS and rear view mirror components. Ensure all components and connectors are connected properly. Using scan tool, clear all SIR and PPS DTC's. Rezero PPS. See PASSENGER PRESENCE SYSTEM REZEROING PROCEDURE . If condition is not corrected, go to step 2. If condition is corrected, system is okay.