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Home >> Acura >> 2003 >> MDX Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Performance System Self-Diagnostics >> Diagnostic Tests >> DTC P0325: Knock Sensor Circuit Malfunction
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DTC P0325: Knock Sensor Circuit Malfunction

CAUTION: When substituting or replacement of PCM is recommended, see PCM REMOVAL & REPLACEMENT  for important precautions.
  1. Turn ignition on. Using Honda PGM Tester or the HDS, do the DTC CLEAR in the CLEAR menu.
  2. Start engine. Hold at 3000 RPM with no load (A/T in Park or Neutral) until radiator fan comes on, then let it idle.
  3. Hold engine at 3000-4000 RPM for at least 60 seconds.
  4. Check for Temporary DTCs or DTCs in the DTC menu. If DTC P0325 is set, go to next step. If any other Temporary DTCs or DTCs are set, troubleshoot those indicated. If DTC P0340 is not set, problem is intermittent, system is OK at this time. Check for poor connections or loose terminals at knock sensor and PCM connectors.
  5. Turn ignition switch off. Disconnect PCM harness connector "A". See Figure . Disconnect KS sub-harness 1-pin connector. Check for continuity between ground and PCM harness connector terminal A26 (Red/Blue wire). See Figure . If continuity is present, repair short in Red/Blue wire between PCM harness connector and KS sub-harness connector. Go to step  11 . If continuity is not present, go to next step.
  6. Connect fused jumper wire between ground and KS sub-harness 1-pin connector. Check for continuity in Red/Blue wire between ground and PCM harness connector terminal A26 (Red/Blue wire). If continuity is present, go to next step. If continuity is not present, repair open in Red/Blue wire between PCM harness connector and KS sub-harness connector. Go to step  8 .
  7. Remove intake manifold.
  8. Check KS sub-harness 1-pin connector and knock sensor for an open or short. If they are OK, go to next step. If they are not OK, repair or replace KS sub-harness. Go to step  11 .
  9. Replace knock sensor.
  10. Install intake manifold.
  11. 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  . Go to next step.
  12. Start engine. Hold at 3000 RPM with no load (A/T in Park or Neutral) until radiator fan comes on, then let it idle.
  13. Hold engine at 3000-4000 RPM for at least 60 seconds.
  14. Check for Temporary DTCs or DTCs in the DTC menu. If any Temporary DTCs or DTCs are set, go to step  16 . If any Temporary DTCs or DTCs are not set, go to next step.
  15. Using the Honda PGM Tester or the HDS, monitor OBD STATUS for DTC P0325 in the DTCs menu. If it is PASSED, troubleshooting is complete. If it FAILED, go to step  1 . If it is NOT COMPLETED, go to step  12 and recheck.
  16. Update the PCM if it does not have the latest software, or substitute a known-good PCM.
  17. Start engine. Hold at 3000 RPM with no load (A/T in Park or Neutral) until radiator fan comes on, then let it idle.
  18. Check for Temporary DTCs or DTCs in the DTC menu. If DTC P0325 is set, check for poor connections or loose terminals at knock sensor and PCM harness 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, PCM was updated, troubleshooting is complete. If PCM was substituted, replace original PCM.
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