DTC Troubleshooting: U129E (V6, PGM-FI System) - Honda Accord CR/CT 2012-2017

DTC Troubleshooting: U129E

DTC U129E: F-CAN Malfunction (PCM-Power Control Unit (PCU))

NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
U129E F-CAN Malfunction (PCM-Power Control Unit (PCU))

DTC check:

DTC check

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

?2.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
U0029 F-CAN Malfunction (BUS-OFF (PCM))
U129E F-CAN Malfunction (PCM-Power Control Unit (PCU))

Are DTC U0029 and U129E indicated at the same time?


	YES

Do the troubleshooting for DTC U0029.?


	NO

Go to step 2.

Problem verification:

Problem verification

?1.	Clear the DTC with the HDS.

?2.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
U129E F-CAN Malfunction (PCM-Power Control Unit (PCU))

Is DTC U129E indicated?


	YES

Go to step 3.


	NO

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the keyless access control unit and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.?

Keyless access system check:

Keyless access system check

?1.	Check for communication to the keyless access system with the HDS.

Does the HDS communicate with the keyless access control unit?


	YES

Go to step 4.


	NO

Go to the symptom troubleshooting for keyless access indicator does not go off or does not come on.?

Open wire check (F-CAN_H line):

Open wire check (F-CAN_H line)

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

?2.	Jump the SCS line with the HDS.

?3.

Disconnect the following connectors.

PCM connector A (51P)

Keyless access control unit connector C (24P)

?4.

Check for continuity between test points 1 and 2.

Test condition	OFF mode
	PCM connector A (51P): disconnected
	Keyless access control unit connector C (24P): disconnected
Test circuit	F-CAN_H
Test point 1	Keyless access control unit connector C (24P) No. 4 (WHT)
Test point 2	PCM connector A (51P) No. 9 (WHT)

Is there continuity?


	YES

Go to step 5.


	NO

Repair an open in the F-CAN_H wire between the PCM (A9) and the keyless access control unit.?

Open wire check (F-CAN_L line):

Open wire check (F-CAN_L line)

?1.

Check for continuity between test points 1 and 2.

Test condition	OFF mode
	PCM connector A (51P): disconnected
	Keyless access control unit connector C (24P): disconnected
Test circuit	F-CAN_L
Test point 1	Keyless access control unit connector C (24P) No. 5 (RED)
Test point 2	PCM connector A (51P) No. 10 (RED)

Is there continuity?


	YES

Replace the keyless access control unit.?


	NO

Repair an open in the F-CAN_L wire between the PCM (A10) and the keyless access control unit.?