DTC Troubleshooting
DTC Troubleshooting: P050A
DTC P050A: Cold Start Idle Air Control System Performance Problem
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information. Initial Inspection and Diagnostic Overview
1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
2. Check for Pending or Confirmed DTCs with the HDS.
Are any Pending or Confirmed DTCs other than P050A indicated?
YES - Go to the indicated DTC's troubleshooting.
NO - Go to step 3.
3. Check for poor connections or a blockage at the intake air duct.
Is it OK?
YES - Go to step 4.
NO - Reconnect or repair the intake air duct, then go to step 20.
4. Check for damage at the air cleaner housing.
Is it OK?
YES - Go to step 5.
NO - Replace the air cleaner housing, Service and Repair then go to step 20.
5. Check for dirt or debris in the air cleaner element.
Is it dirty?
YES - Replace the air cleaner element or remove the debris, Service and Repair then go to step 20.
NO - Go to step 6.
6. Let the engine cool until the value of ECT SENSOR 1 is 122 °F (50 °C) or less.
7. Clear the DTC with the HDS.
8. Start the engine, and let it idle for 10 seconds or more.
9. Monitor the OBD STATUS for DTC P050A in the DTCs MENU with the HDS.
Does the screen indicate FAILED?
YES - Go to step 10.
NO - If the screen indicates PASSED, intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the throttle body, the MAF sensor/IAT sensor, and the PCM. If the screen indicates EXECUTING, keep idling until a result comes on. If the screen indicates OUT OF CONDITION, go to step 6.
10. Do the ETCS TEST in the INSPECTION MENU with the HDS.
Is the THROTTLE ACTUATOR CONTROL VALVE normal?
YES - Go to step 11.
NO - Replace the throttle body, Removal and Replacement then go to step 20.
11. Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
12. Monitor the ENGINE SPEED in the DATA LIST with the HDS, and hold the engine speed at 2,500 rpm for at least 30 seconds.
13. While holding the engine speed at 2,500 rpm, check the MAF SENSOR in the DATA LIST with the HDS.
Is there about 11.0-15.5 gm/s (J35Z6 engine) or 11.8-16.6 gm/s (J37A4 engine)?
YES - Go to step 14.
NO - Replace the MAF sensor/IAT sensor, Service and Repair then go to step 20.
14. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
15. Allow the engine to cool to the ambient temperature.
16. Note the ambient temperature.
17. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
18. Note the value of IAT SENSOR quickly in the DATA LIST with the HDS.
19. Compare the value of the IAT SENSOR and the ambient temperature.
Does the value of the IAT SENSOR differ 5.4 °F (3 °C) or more from ambient temperature?
YES - Replace the MAF sensor/IAT sensor, Service and Repair then go to step 20.
NO - Check for dirt, carbon, or damage in the throttle bore. If there is dirt or carbon, clean the throttle body, Procedures then go to step 20. If there is damage in the throttle bore, replace the throttle body, Removal and Replacement then go to step 20.
20. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
21. Reset the PCM with the HDS.
22. Do the PCM idle learn procedure. PCM Idle Learn Procedure
23. Let the engine cool until the value of ECT SENSOR 1 is 122 °F (50 °C) or less.
24. Start the engine, and let it idle for 10 seconds or more.
25. Check for Pending or Confirmed DTCs with the HDS.
Is DTC P050A indicated?
YES - Check for poor connections or loose terminals at the throttle body, the MAF sensor/IAT sensor, and the PCM, then go to step 1.
NO - Go to step 26.
26. Monitor the OBD STATUS for DTC P050A in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete. If any other Pending or Confirmed DTCs were indicated in step 25, go to the indicated DTC's troubleshooting.
NO - If the screen indicates FAILED, check for poor connections or loose terminals at the throttle body, the MAF sensor/IAT sensor, and the PCM, then go to step 1. If the screen indicates EXECUTING, keep idling until a result comes on. If the screen indicates OUT OF CONDITION, go to step 23.