Diagnostic Procedures
- Did you perform the Diagnostic System Check-Engine Controls? If yes, go to next step. If no, see DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM.
- Turn ON the ignition, with the engine OFF. With a scan tool, clear the DTCs. With a scan tool, observe the DTC information for 30 seconds. Are DTCs P0030, P0036, P1031, and/or P1032 set? If yes, see DTC P0030: HO2S HEATER CONTROL CIRCUIT SENSOR 1 . If no, go to next step.
- Start the engine and bring to operating temperature. With a scan tool, clear the DTCs. With a scan tool, observe the DTC information for 30 seconds. Does DTC P0036 set? If yes, go to next step. If no, see INTERMITTENT CONDITIONS under SELF-DIAGNOSTIC SYSTEM.
- Turn OFF the ignition. Disconnect the HO2S bank 1 sensor 2 harness connector. Turn ON the ignition, with the engine OFF. With a test lamp connected to ground, probe the ignition supply voltage circuit at the HO2S bank 1 sensor 2 harness connector. Does the test lamp illuminate? If yes, go to next step. If no, go to step 11.
- With a test lamp connected to battery voltage, probe the HO2S bank 1 sensor 2 heater low control circuit. Does the test lamp illuminate? If yes, go to next step. If no, go to step 7.
- Leave the test lamp connected between battery voltage and the HO2S bank 1 sensor 2 heater low control circuit. Turn OFF the ignition. Disconnect the PCM connectors. Turn ON the ignition, with the engine OFF. Does the test lamp illuminate? If yes, go to step 13. If no, go to step 15.
- Leave the test lamp connected between battery voltage and the HO2S bank 1 sensor 2 heater low control circuit. Turn ON the ignition, with the engine OFF. With a scan tool, command the HO2S heater driver 4 ON and OFF. Does the test lamp turn ON and OFF? If yes, go to step 12. If no, go to next step.
- Test the HO2S bank 1 sensor 2 heater low control circuit for an open. Did you find and correct the condition? If yes, go to step 16. If no, go to next step.
- Test the HO2S bank 1 sensor 2 heater low control circuit for a short to voltage. Did you find and correct the condition? If yes, go to step 16. If no, go to next step.
- Test the HO2S bank 1 sensor 2 heater low control circuit for poor connections at the PCM. Did you find and correct the condition? If yes, go to step 16. If no, go to step 15.
- Repair the open in the ignition supply voltage circuit to the HO2S bank 1 sensor 2. After repairs, go to step 16.
- Test for poor connections at the HO2S bank 1 sensor 2 connector. Did you find and correct the condition? If yes, go to step 16. If no, go to step 14.
- Repair the short to ground in the HO2S bank 1 sensor 2 heater low control circuit. After repairs, go to step 16.
- Replace HO2S bank 1 sensor 2. After repairs, go to step 16.
- Replace the PCM. See appropriate REMOVAL, OVERHAUL & INSTALLATION article. Reprogram PCM. See POWERTRAIN CONTROL MODULE under PROGRAMMING. After repairs, go to next step.
- Clear the DTCs with a scan tool. Turn OFF the ignition for 30 seconds. Start the engine. Operate the vehicle within the Conditions for Running DTC. Does the DTC run and pass? If yes, go to next step. If no, go to step 2.
- Observe the stored information, Capture Info with a scan tool. Does the scan tool display any DTCs that you have not diagnosed? If yes, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.