DTC Troubleshooting: P0141 (L4) - Honda Accord CR/CT 2012-2017

DTC Troubleshooting: P0141

DTC P0141: Secondary HO2S (Sensor 2) Heater Circuit Malfunction

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P0141 Secondary HO2S (Sensor 2) Heater Circuit Malfunction

Problem verification:

Problem verification

?1.	Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?2.	Clear the DTC with the HDS.

?3.	Start the engine, and let it idle.

?4.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P0141 Secondary HO2S (Sensor 2) Heater Circuit Malfunction

Is DTC P0141 indicated?


	YES

The failure is duplicated. Go to step 2.


	NO

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at secondary HO2S (Sensor 2), and the PCM.?

Determine possible failure area (IG1 ACG line, others):

Determine possible failure area (IG1 ACG line, others)

?1.	Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.

Check the following fuse.

Fuse	No. B13 (15 A)
Location	Under-dash fuse/relay box

Is the fuse OK?


	YES

The IG1 ACG wire is not shorted. Go to step 3.


	NO

Repair a short in the IG1 ACG wire between the No. B13 (15 A) fuse in the under-dash fuse/relay box and secondary HO2S (Sensor 2). If the IG1 ACG line is OK, replace the under-dash fuse/relay box. Also replace the No. B13 (15 A) fuse, then do the repair verification.

Secondary HO2S (Sensor 2) internal heater resistance check:

Secondary HO2S (Sensor 2) internal heater resistance check

?1.

Disconnect the following connector.

Secondary HO2S (Sensor 2) 4P connector

?2.

At the sensor side, measure the resistance between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	Secondary HO2S (Sensor 2) 4P connector: disconnected
Test circuit	IG1 ACG, SO2 HT
Test point 1	Secondary HO2S (Sensor 2) 4P connector No. 3 (secondary HO2S (Sensor 2) side)
Test point 2	Secondary HO2S (Sensor 2) 4P connector No. 4 (secondary HO2S (Sensor 2) side)

Is there 5.4?6.6 ? at room temperature?


	YES

Go to step 4.


	NO

Replace secondary HO2S (Sensor 2), then do the repair verification.

Secondary HO2S (Sensor 2) internal circuit check:

Secondary HO2S (Sensor 2) internal circuit check

?1.

At the sensor side, check for continuity under the following conditions.

Test condition	IG LOCK (0) or OFF mode
	Secondary HO2S (Sensor 2) 4P connector: disconnected
Test circuit	IG1 ACG
Test point 1	Secondary HO2S (Sensor 2) 4P connector No. 3 (secondary HO2S (Sensor 2) side)
Test point 2	Body ground

Test circuit	SO2 HT
Test point 1	Secondary HO2S (Sensor 2) 4P connector No. 4 (secondary HO2S (Sensor 2) side)
Test point 2	Body ground

Is there continuity?


	YES

Replace secondary HO2S (Sensor 2), then do the repair verification.


	NO

Go to step 5.

Shorted wire check (SO2 HT line):

Shorted wire check (SO2 HT line)

?1.	Jump the SCS line with the HDS.

?2.

Disconnect the following connector.

PCM connector C (51P)

?3.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	Secondary HO2S (Sensor 2) 4P connector: disconnected
	PCM connector C (51P): disconnected
Test circuit	SO2 HT
Test point 1	PCM connector C (51P) No. 9 (BLK/WHT)
Test point 2	Body ground

Is there continuity?


	YES

Repair a short in the SO2 HT wire between the PCM (C9) and secondary HO2S (Sensor 2), then do the repair verification.


	NO

The SO2 HT wire is not shorted. Go to step 6.

Open wire check (SO2HT/SO2 HT line):

Open wire check (SO2HT/SO2 HT line)

?1.

Check for continuity between test points 1 and 2.

Test condition	IG LOCK (0) or OFF mode
	Secondary HO2S (Sensor 2) 4P connector: disconnected
	PCM connector C (51P): disconnected
Test circuit	SO2HT/SO2 HT
Test point 1	Secondary HO2S (Sensor 2) 4P connector No. 4 (LT BLU)
Test point 2	PCM connector C (51P) No. 9 (BLK/WHT)

Is there continuity?


	YES

The SO2HT/SO2 HT wire is OK. Go to step 7.


	NO

Repair an open in the SO2HT/SO2 HT wire between the PCM (C9) and secondary HO2S (Sensor 2), then do the repair verification.

Open wire check (IG1 ACG line):

Open wire check (IG1 ACG line)

?1.	Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?2.

Measure the voltage between test points 1 and 2.

Test condition	IG ON (II) or ON mode
	Secondary HO2S (Sensor 2) 4P connector: disconnected
Test circuit	IG1 ACG
Test point 1	Secondary HO2S (Sensor 2) 4P connector No. 3 (PNK)
Test point 2	Body ground

Is there battery voltage?


	YES

The IG1 ACG wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then do the repair verification.


	NO

Repair an open in the IG1 ACG wire between the No. B13 (15 A) fuse and secondary HO2S (Sensor 2), then do the repair verification.

Repair verification (OBD STATUS check):

?1.	Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.	Reconnect all connectors.

?3.	Exit the SCS mode with the HDS.

?4.	Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?5.	Reset the PCM with the HDS.

?6.	Do the PCM idle learn procedure.

?7.

Monitor the OBD STATUS for DTC P0141 in the DTCs MENU with the HDS.

DTC Description	OBD STATUS
P0141 Secondary HO2S (Sensor 2) Heater Circuit Malfunction

Does the HDS indicate PASSED, FAILED, or NOT COMPLETED?


	PASSED

Troubleshooting is complete. If the PCM was substituted, replace the original PCM. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.?


	FAILED

Go to step 1 and recheck. If the PCM was updated, substitute a known-good PCM, then check the OBD STATUS again.


	NOT COMPLETED

Meet the test condition, and check the OBD STATUS again.