P0155
DTC P0155: Front A/F sensor (Bank 2, Sensor 1) Heater Circuit MalfunctionNOTE: Information marked with an asterisk (*) applies to the front bank (Bank 2).
1. Turn the ignition switch ON (II).
2. Clear the DTC with the HDS.
3. Start the engine.
4. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P0135 and/or P0155* indicated?
YES - Go to step 5.
NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM.
5. Turn the ignition switch OFF.
6. Check the No.9 LAFHT (15 A)fuse in the under-hood subfuse box.
Is the fuse blown?
YES - Repair short in the wire between the A/F sensors, A/F sensor relay and the fuse, then go to step 25.
NO - Go to step 7.
7. Disconnect the A/F sensor (Sensor 1) 8P connector.
8. At the sensor side, measure resistance between the A/F sensor (Sensor 1) 8P connector terminals No.1 and No.2.
Is there 2.5 - 3.2 Ohms at room temperature?
YES - Go to step 9.
NO - Go to step 24.
9. Check for continuity between each terminal at the A/F sensor (Sensor 1) 8P connector and body ground.
Is there continuity?
YES - Go to step 24.
NO - Go to step 10.
10. Check for continuity between the A/F sensor (Sensor 1) 8P connector terminals No.1 and No.3, and No.4, No.6, No.7, and No.8 individually.
Is there continuity?
YES - Go to step 24.
NO - Go to step 11.
11. Jump the SCS line with the HDS.
12. Disconnect PCM connector A (73P).
13. Check for continuity between PCM connector terminals A57 (A58)* and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (A57 (A58)*) and the A/F sensor (Sensor 1), then go to step 25.
NO - Go to step 14.
14. Connect the A/F sensor (Sensor 1) 8P connector terminal No.2 to body ground with a jumper wire.
15. Check for continuity between PCM connector terminal A57 (A58)* and body ground.
Is there continuity?
YES - Go to step 16.
NO - Repair open in the wire between the PCM (A57 (A58)*) and the A/F sensor (Sensor 1),then go to step 25.
16. Connect the A/F sensor (Sensor 1) 8P connector terminal No.1 to body ground with a jumper wire.
17. Remove the A/F sensor relay (A).
18. Check for continuity between A/F sensor relay terminal No.2 and body ground
Is there continuity?
YES - Go to step 19.
NO - Repair open in the wire between the A/F sensor (Sensor 1) and the A/F sensor relay, then go to step 25.
19. Disconnect PCM connector B (56P).
20. Check for continuity between PCM connector terminal B10 and body ground
Is there continuity?
YES - Repair short in the wire between the PCM (B10) and the A/F sensor relay, then go to step 25.
NO - Go to step 21.
21. Connect the A/F sensor relay 4P connector No.3 terminal and body ground with a jumper wire.
22. Check for continuity between PCM connector terminal B10 and the A/F sensor relay terminal No.3.
Is there continuity?
YES - Go to step 23.
NO - Repair open in the wire between the PCM (B10) and the A/F sensor relay, then go to step 25.
23. Test the A/F sensor relay.
Is the A/F sensor relay OK ?
YES - Go to step 30.
NO - Replace the A/F sensor relay, then go to step 25.
24. Replace the A/F sensor (Sensor 1).
25. Turn the ignition switch ON (II).
26. Reset the PCM with the HDS.
27. Do the PCM idle learn procedure.
28. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0135 and/or P0155* is indicated, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - Go to step 29.
29. Monitor the OBD STATUS for DTC P0135 and/or P0155* in the DTCs MENU with the HDS.
Does the screen indicate PASSED?
YES - Troubleshooting is complete.
NO - If the screen indicates FAILED, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM, then go to step 1. If the screen indicates NOT COMPLETED, go to step 26 and recheck.
30. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
31. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - If DTC P0135 and/or P0155* is indicated, check for poor connections or loose terminals at the A/F sensor (Sensor 1) and the PCM, then go to step 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.
NO - If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM.