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DTC P0141 Or DTC P0161

Code Definition

CAUTION: When substituting or replacement of PCM is recommended, see PCM REMOVAL & REPLACEMENT  for important precautions.
NOTE: This test covers both Front and Rear secondary HO2S (Sensor 2). The information will be shown Rear (Bank 1) first and Front (Bank 2) second. When discussion of PCM harness connector terminals arises, Rear secondary HO2S (Sensor 2) terminals will precede Front secondary HO2S (Sensor 2) terminals. Also, Front secondary HO2S (Sensor 2) 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 P0141 and/or (P0161) are set, go to next step. If DTCs P0141 and/or (P0161) are not set, problem is intermittent, system is OK at this time. Check for poor connections or loose terminals at secondary HO2S (Sensor 2) 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 secondary HO2S (Sensor 2) and A/F sensor relay and the fuse. Go top step  14 . If fuse is not blown, go to next step.
  5. Disconnect the secondary HO2S (Sensor 2) 4-pin harness connector. See Fig 1 . At component side, measure resistance between the secondary HO2S (Sensor 2) 4-pin harness connector terminals No. 3 and 4. If there is between 5.4-6.6 ohms at room temperature, go to next step. If there is not between 5.4-6.6 ohms at room temperature, go to step  13 .
  6. Check for continuity between ground and secondary HO2S (Sensor 2) 4-pin harness connector terminal No. 3 and 4 individually. If there is continuity, go to step  13 . If there is no continuity, go to next step.
  7. Disconnect PCM harness connector "A". See Figure . Check continuity between ground and PCM harness connector "A" terminal A59 (A60). If continuity is present, repair short in wire(s) between PCM harness connector "A" terminal A59 (A60) and secondary HO2S (Sensor 2). Go to step  14 . If continuity is not present, go to next step.
  8. With a fused jumper wire, connect secondary HO2S (Sensor 2) connector terminal No. 3 to ground. Check continuity between ground and PCM harness connector "A" terminal A59 (A60). If continuity is present, go to next step. If continuity is not present, repair open in wire(s) between PCM harness connector "A" terminal A59 (A60) and secondary HO2S (Sensor 2). Go to step  14 .
  9. With a fused jumper wire, connect secondary HO2S (Sensor 2) connector terminal No. 4 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 secondary HO2S (Sensor 2) and the A/F sensor relay. Go to step  14 .
  10. 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  14 . If continuity is not present, go to next step.
  11. With a fused jumper wire, connect A/F sensor relay harness connector terminal No. 3 (Orange wire) to ground. Check continuity between ground 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  13 .
  12. Test A/F sensor relay. If the A/F sensor relay is OK, go to step  17 . If the A/F sensor relay is not OK, replace the A/F sensor relay. Go to step  14 .
  13. Replace secondary HO2S (Sensor 2).
  14. 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  .
  15. Check for Temporary DTCs or DTCs in the DTC menu. If DTCs P0141 and/or (P0161) are set, check for poor connections or loose terminals at secondary HO2S (Sensor 2) 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.
  16. Using the Honda PGM Tester or the HDS, monitor OBD STATUS for DTCs P0141 and/or (P0161) in the DTCs menu. If it is PASSED, troubleshooting is complete. If it FAILED, check for poor connections or loose terminals at secondary HO2S (Sensor 2) and PCM connector Go to step  1 . If it is NOT COMPLETED, go to step  15 and recheck.
  17. Update the PCM if it does not have the latest software, or substitute a know-good PCM.
  18. Check for Temporary DTCs or DTCs in the DTC menu. If DTC P0141 and/or (P0161) are set, check for poor connections or loose terminals at secondary HO2S (Sensor 2) 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 Secondary Heated Oxygen Sensor Connector & Terminals (Sensor 2)
G96B09591Courtesy of AMERICAN HONDA MOTOR CO., INC.
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