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DTC P0135 Or DTC P0155

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CAUTION: When substituting or replacement of PCM is recommended, see PCM REMOVAL & REPLACEMENT  for important precautions.
NOTE: This test covers both Front and Rear Air Fuel Ratio (A/F) sensors. The information will be shown Rear (Bank 1) first and Front (Bank 2) second. When discussion of PCM harness connector terminals arises, Rear (A/F) ratio sensor terminals will precede Front A/F ratio sensor terminals. Also, Front A/F ratio sensor terminal information will be enclosed in parantheses ( ).
  1. Turn ignition on. Using Honda PGM Tester or the HDS, do the DTC CLEAR in the CLEAR menu.
  2. Start engine with no load (A/T in Park or Neutral). Run until the radiator fan comes on, then let engine idle.
  3. Check for Temporary DTCs or DTCs in the DTC menu. If DTCs P0135 and/or (P0155) are set, go to next step. If DTCs P0135 and/or (P0155) are not set, problem is intermittent, system is OK at this time. Check for poor connections or loose terminals at A/F sensor (Sensor 1) and PCM connector.
  4. Turn ignition switch off. Check No. 9 LAFHT (15-amp) fuse in the under-hood sub-fuse box. If it is blown, repair short in wire between Air Fuel Ratio sensor and A/F sensor relay and the fuse. Go top step  15 . If fuse is not blown, go to next step.
  5. Disconnect the A/F sensor 8-pin harness connector. See Fig 1 . At component side measure resistance between the A/F sensor 8-pin harness connector terminals No. 1 and 2. If there is between 2.5-3.2 ohms at room temperature, go to next step. If there is not between 2.5-3.2 ohms at room temperature, go to step  14 .
  6. Check for continuity between ground and each A/F sensor 8-pin harness connector terminal individually. If there is continuity, go to step  14 . If there is no continuity, go to next step.
  7. Check for continuity between the A/F sensor 8-pin harness connector terminal No. 1 and the rest, 3, 4, 6, 7 and 8 individually. If there is continuity, repair short in wire between go to step  14 . If there is no continuity, go to next step.
  8. Disconnect PCM harness connector "A". See Figure . Check continuity between ground and PCM harness connector "A" terminal A57 (A58). If continuity is present, repair short in wire(s) between PCM harness connector "A" terminal A57 (A58) and A/F sensor (Sensor 1). Go to step  15 . If continuity is not present, go to next step.
  9. With a fused jumper wire, connect A/F sensor (Sensor 1) connector terminal No. 2 to ground. Check continuity between ground and PCM harness connector "A" terminal A57 (A58). If continuity is present, go to next step. If continuity is not present, repair open in wire(s) between PCM harness connector "A" terminal A57 (A58) and A/F sensor (Sensor 1). Go to step  15 .
  10. With a fused jumper wire, connect A/F sensor (Sensor 1) connector terminal No. 1 to ground. Remove the A/F sensor relay. Check continuity between ground and A/F sensor relay harness connector terminal No. 2 (White/Black wire). If continuity is present, go to next step. If continuity is not present, repair open in wire between A/F sensor (Sensor 1) and the A/F sensor relay. Go to step  15 .
  11. Disconnect PCM harness connector "B". See Figure . Check continuity between ground and PCM harness connector "B" terminal B10 (Orange wire). If continuity is present, repair short in wire between PCM harness connector "B" terminal B10 (Orange wire) and A/F sensor relay. Go to step  15 . If continuity is not present, go to next step.
  12. Check continuity between A/F sensor relay terminal No. 3 and PCM harness connector "B" terminal B10 (Orange wire). If continuity is present, go to next step. If continuity is not present, repair open in wire between PCM harness connector "B" terminal B10 (Orange wire) and A/F sensor relay. Go to step  15 .
  13. Test A/F sensor relay. If the A/F sensor relay is OK, go to step  18 . If the A/F sensor relay is not OK, replace the A/F sensor relay. Go to step  15 .
  14. Replace A/F sensor (Sensor 1).
  15. Turn ignition on. With the Honda PGM tester or the HDS, do PCM RESET in the CLEAR menu. Do the PCM idle learn procedure. See PCM IDLE LEARN PROCEDURE  .
  16. Check for Temporary DTCs or DTCs in the DTC menu. If DTCs P0135 and/or (P0155) are set, check for poor connections or loose terminals at A/F sensor (Sensor 1) and PCM connector, go to step  1 . If any other Temporary DTCs or DTCs are set, troubleshoot those indicated. If there are no Temporary DTCs or DTCs set, go to next step.
  17. Using the Honda PGM Tester or the HDS, monitor OBD STATUS for DTCs P0135 and/or (P0155) in the DTCs menu. If it is PASSED, troubleshooting is complete. If it FAILED, check for poor connections or loose terminals at A/F sensor (Sensor 1) and PCM connector Go to step  1 . If it is NOT COMPLETED, go to step  15 and recheck.
  18. Update the PCM if it does not have the latest software, or substitute a know-good PCM.
  19. Check for Temporary DTCs or DTCs in the DTC menu. If DTC P0135 and/or (P0155) are set, check for poor connections or loose terminals at A/F sensor (Sensor 1) and PCM connectors. Go to step  1 . If any other Temporary DTCs or DTCs are set, troubleshoot those indicated. If Temporary DTCs or DTCs are not set, PCM was updated, troubleshooting is done. If PCM was substituted, replace the original PCM.
Fig 1: Identifying Air Fuel Ratio Sensor Connector & Terminals (Sensor 1)
G00188375Courtesy of AMERICAN HONDA MOTOR CO., INC.
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