DTC P0139 Or DTC P0159

Code Definition

DTC P0139: Rear Secondary Heated Oxygen Sensor Slow Response (Bank 1, Sensor 2)
DTC P0159: Front Secondary Heated Oxygen Sensor Slow Response (Bank 2, Sensor 2)

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 ( ).

Turn ignition on. Using Honda PGM Tester or the HDS, do the DTC CLEAR in the CLEAR menu.
Start engine. Hold engine at 3000 RPM with no load in (Park or Neutral) until the radiator fan comes on, then let engine idle.
Test drive vehicle with throttle fully opened, then decelerate with throttle fully closed for 3 seconds.
Using the Honda PGM Tester or the HDS, monitor OBD STATUS for DTCs P0139 and/or (P0159) in the DTCs menu. If it is PASSED, problem is intermittent, system is OK at this time. If it FAILED, go to next step. If it is EXECUTING, continue driving condition until a result comes in. If it is OUT OF CONDITION, go to step 2 and recheck.
Turn ignition off.
Replace secondary HO2S (Sensor 2).
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 .
Test drive vehicle with throttle fully opened, then decelerate with throttle fully closed for 3 seconds.
Check for Temporary DTCs or DTCs in the DTC menu. If DTCs P0139 and/or (P0159) 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.
Using the Honda PGM Tester or the HDS, monitor OBD STATUS for P0139 and/or (P0159) 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 8 and recheck.