DTC Troubleshooting: P0141, P0161 (V6) - Honda Accord CR/CT 2012-2017

DTC Troubleshooting: P0141, P0161

DTC P0141: Rear Secondary HO2S (Bank 1, Sensor 2) Heater Circuit Malfunction
DTC P0161: Front Secondary HO2S (Bank 2, Sensor 2) Heater Circuit Malfunction

NOTE:

	Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information.
	Information marked with an asterisk (*) applies to the front bank (Bank 2).

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P0141 Rear Secondary HO2S (Bank 1, Sensor 2) Heater Circuit Malfunction
P0161 Front Secondary HO2S (Bank 2, Sensor 2) Heater Circuit Malfunction

Problem verification:

Problem verification

?1.	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 Rear Secondary HO2S (Bank 1, Sensor 2) Heater Circuit Malfunction
P0161 Front Secondary HO2S (Bank 2, Sensor 2) Heater Circuit Malfunction

Is DTC P0141 and/or P0161^* 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 (IG (LAF O2)/FI SUB RLY OUT line, others):

Determine possible failure area (IG (LAF O2)/FI SUB RLY OUT line, others)

?1.	Press the engine start/stop button to select the OFF mode.

?2.

Check the following fuse.

Fuse	No. A7 (15 A)
Location	Under-hood fuse/relay box

Is the fuse OK?


	YES

The IG (LAF O2)/FI SUB RLY OUT wire is not shorted. Go to step 3.


	NO

Go to step 10.

Relay check:

?1.	Remove the PGM-FI subrelay (A) from the under-hood fuse/relay box.

?2.	Test the PGM-FI subrelay.

Is the relay OK?


	YES

The PGM-FI subrelay is OK. Go to step 4.


	NO

Replace the PGM-FI subrelay, 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 connectors.

Front secondary HO2S (Sensor 2) 4P connector

Rear secondary HO2S (Sensor 2) 4P connector

?2.

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

Test condition	OFF mode
	PGM-FI subrelay: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
Test circuit	SO2HT B1 (SO2HT B2)^*, IG (LAF O2)
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)

Rear bank (Bank 1):

Front bank (Bank 2) (J35Y1 engine):

Front bank (Bank 2) (J35Y2 engine):

Is there 5.4?6.6 ? at room temperature?


	YES

Go to step 5.


	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	OFF mode
	PGM-FI subrelay: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
Test circuit	SO2HT B1 (SO2HT B2)^*
Test point 1	Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 4 (secondary HO2S (Sensor 2) side)
	J35Y1 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 3 (secondary HO2S (Sensor 2) side)*
	J35Y2 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 4 (secondary HO2S (Sensor 2) side)^*
Test point 2	Body ground

Test circuit	IG (LAF O2)
Test point 1	Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 3 (secondary HO2S (Sensor 2) side)
	J35Y1 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 4 (secondary HO2S (Sensor 2) side)^*
	J35Y2 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 3 (secondary HO2S (Sensor 2) side)*
Test point 2	Body ground

Rear bank (Bank 1):

Front bank (Bank 2) (J35Y1 engine):

Front bank (Bank 2) (J35Y2 engine):

Is there continuity?


	YES

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


	NO

Go to step 6.

Shorted wire check (SO2HT B1 (SO2HT B2)^* line):

Shorted wire check (SO2HT B1 (SO2HT B2)^* 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	OFF mode
	PGM-FI subrelay: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
	PCM connector C (51P): disconnected
Test circuit	SO2HT B1 (SO2HT B2)^*
Test point 1	PCM connector C (51P) No. 5 (PUR)
	PCM connector C (51P) No. 7 (RED)^*
Test point 2	Body ground

Is there continuity?


	YES

Repair a short in the SO2HT B1 (SO2HT B2)^* wire between the PCM (C5 (C7)^*) and secondary HO2S (Sensor 2), then do the repair verification.


	NO

The SO2HT B1 (SO2HT B2)^* wire is not shorted. Go to step 7.

Open wire check (SO2HT B1 (SO2HT B2)^* line):

Open wire check (SO2HT B1 (SO2HT B2)^* line)

?1.

Check for continuity between test points 1 and 2.

Test condition	OFF mode
	PGM-FI subrelay: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
	PCM connector C (51P): disconnected
Test circuit	SO2HT B1 (SO2HT B2)^*
Test point 1	Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 4 (PUR)
	Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 3 (RED)^*
Test point 2	PCM connector C (51P) No. 5 (PUR)
	PCM connector C (51P) No. 7 (RED)^*

Rear bank (Bank 1):

Front bank (Bank 2):

Is there continuity?


	YES

The SO2HT B1 (SO2HT B2)^* wire is OK. Go to step 8.


	NO

Repair an open in the SO2HT B1 (SO2HT B2)^* wire between the PCM (C5 (C7)^*) and secondary HO2S (Sensor 2), then do the repair verification.

Open wire check (IG (LAF O2)/FI SUB RLY OUT line):

Open wire check (IG (LAF O2)/FI SUB RLY OUT line)

?1.

Check for continuity between test points 1 and 2.

Test condition	OFF mode
	PGM-FI subrelay: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
	PCM connector C (51P): disconnected
Test circuit	IG (LAF O2)/FI SUB RLY OUT
Test point 1	PGM-FI subrelay 4P socket No. 2
Test point 2	Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 3 (PNK)
	J35Y1 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 4 (PNK)^*
	J35Y2 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 3 (PNK)*

Rear bank (Bank 1):

Front bank (Bank 2) (J35Y1 engine):

Front bank (Bank 2) (J35Y2 engine):

Are there continuity?


	YES

The IG (LAF O2)/FI SUB RLY OUT is not open. Go to step 9.


	NO

Repair an open in the IG (LAF O2)/FI SUB RLY OUT wire between secondary HO2S (Sensor 2) and the PGM-FI subrelay, then do the repair verification.

Open wire check (FI SUB RLY CL- line):

Open wire check (FI SUB RLY CL- line)

?1.

Disconnect the following connector.

PCM connector A (51P)

?2.

Check for continuity between test points 1 and 2.

Test condition	OFF mode
	PGM-FI subrelay: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
	PCM connector C (51P): disconnected
	PCM connector A (51P): disconnected
Test circuit	FI SUB RLY CL-
Test point 1	PGM-FI subrelay 4P socket No. 4
Test point 2	PCM connector A (51P) No. 14 (PNK)

Is there continuity?


	YES

The FI SUB RLY CL- 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 FI SUB RLY CL- wire between the PGM-FI subrelay and the PCM (A14), then do the repair verification.

10.

Shorted wire check (IG (LAF O2)/FI SUB RLY OUT line):

Shorted wire check (IG (LAF O2)/FI SUB RLY OUT line)

?1.	Remove the PGM-FI subrelay (A) and the No. A23 (7.5 A) fuse from the under-hood fuse/relay box.

?2.

Disconnect the following connectors.

Front and rear secondary HO2S (Sensor 2) 4P connectors

Front and rear A/F sensor (Sensor 1) 6P connectors

EVAP canister vent shut valve 2P connector

?3.

Check for continuity between test points 1 and 2.

Test condition	OFF mode
	PGM-FI subrelay: disconnected
	No. A23 (7.5 A) fuse: disconnected
	Front and rear secondary HO2S (Sensor 2) 4P connectors: disconnected
	Front and rear A/F sensor (Sensor 1) 6P connectors: disconnected
	EVAP canister vent shut valve 2P connector: disconnected
Test circuit	IG (LAF O2)
Test point 1	Rear secondary HO2S (Bank 1, Sensor 2) 4P connector No. 3 (PNK)
	J35Y1 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 4 (PNK)*
	J35Y2 engine: Front secondary HO2S (Bank 2, Sensor 2) 4P connector No. 3 (PNK)^*
Test point 2	Body ground

Rear bank (Bank 1):

Front bank (Bank 2) (J35Y1 engine):

Front bank (Bank 2) (J35Y2 engine):

Is there continuity?


	YES

Repair a short in the IG (LAF O2)/FI SUB RLY OUT wire between the PGM-FI subrelay and secondary HO2S (Sensor 2), then do the repair verification.


	NO

The IG (LAF O2)/FI SUB RLY OUT wire is OK. Check the under-hood fuse/relay box, and replace it if needed. Also replace the No. A7 (15 A) fuse, then do the repair verification.

Repair verification (OBD STATUS check):

?1.	Press the engine start/stop button to select the OFF mode.

?2.	Reconnect all connectors.

?3.	Exit the SCS mode with the HDS.

?4.	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 and/or P0161^* in the DTCs MENU with the HDS.

DTC Description	OBD STATUS
P0141 Rear Secondary HO2S (Bank 1, Sensor 2) Heater Circuit Malfunction
P0161 Front Secondary HO2S (Bank 2, Sensor 2) Heater Circuit Malfunction

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


	PASSED (P0141)

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.?


	PASSED (P0161)

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 (P0141)

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


	FAILED (P0161)

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.