DTC U0101, U0104, U0122, U0128, U0129, U0131, U0132, U0151, U0155, U129E (PGM-FI System (1.5 L Engine): With ACC)

WARNING: This page is about a different car, the 2022 Honda Accord, 2021 Honda Accord, 2020 Honda Accord, 2019 Honda Accord, and 2018 Honda Accord. However, it is still accessible from the selected car via links, so may be relevant.

DTC U0101 : F-CAN Malfunction (PCM-TCM)DTC U0104 : F-CAN Malfunction (PCM-Driving Support System Control Unit)DTC U0122 : F-CAN Malfunction (PCM-VSA Modulator-Control Unit)DTC U0128 : F-CAN Malfunction (PCM-Electric Parking Brake Control Unit)DTC U0129 : F-CAN Malfunction (PCM-Electric Brake Booster)DTC U0131 : F-CAN Malfunction (PCM-EPS Control Unit)DTC U0132 : F-CAN Malfunction (PCM-Adaptive Damper Control Unit)DTC U0151 : F-CAN Malfunction (PCM-SRS Unit)DTC U0155 : F-CAN Malfunction (PCM-Gauge Control Module)DTC U129E : F-CAN Malfunction (PCM-Power Control Unit (PCU))

NOTE:

Before you troubleshoot, review the general troubleshooting information .
According to the detected DTC (s), check for the power circuit and the ground circuit of the control unit which cannot communicate with the PCM.
Before disconnecting the SRS unit connector and the electric brake booster connectors, do the 12 volt battery terminal disconnection procedure , and wait for at least 3 minutes.
Before disconnecting the electric brake booster connector, turn the vehicle to the OFF (LOCK) mode with the driver's door open, and wait for at least 3 minutes (do not close the door).

DTC Description	Confirmed DTC	Pending DTC
U0101 F-CAN Malfunction (PCM-TCM)
U0104 F-CAN Malfunction (PCM-Driving Support System Control Unit)
U0122 F-CAN Malfunction (PCM-VSA Control Module Unit)
U0128 F-CAN Malfunction (PCM-Electric Parking Brake Control Unit)
U0129 F-CAN Malfunction (PCM-Electric Brake Booster)
U0131 F-CAN Malfunction (PCM-EPS Control Unit)
U0132 F-CAN Malfunction (PCM-Adaptive Damper Control Unit)
U0151 F-CAN Malfunction (PCM-SRS Unit)
U0155 F-CAN Malfunction (PCM-Gauge Control Module)
U129E F-CAN Malfunction (PCM-Power Control Unit (PCU))

DTC (PGM-FI)

CAN gateway system DTC check

-1. Turn the vehicle to the ON mode, and wait 6 seconds.

-2. Check for CAN gateway system DTCs with the HDS.

DTC Description	DTC

DTC (CAN gateway)

Is any DTC indicated?

YES

Go to the troubleshooting for CAN gateway system DTCs .

Go to step 2.

F-CAN circuit communication check (Receiving control unit)
-1. Select the Function Test in the CAN Gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

F-CAN Bus Connected Unit Check

Which result is indicated?

Bus A is Not Available

Go to step 3.

Bus B is Not Available

Go to step 4.

Bus A and B are Available

Go to step 5.

Open wire check (F-CAN A_H line, F-CAN A_L line) 1

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. Jump the SCS line with the HDS, and wait more than 1 minute.

-3. Disconnect the following connectors.

CAN gateway 16P connector

PCM connector A (50P)

-4. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	PCM connector A (50P): disconnected
Test point 1	CAN gateway 16P connector (female terminal) No. 3:
Test point 2	PCM connector A (50P) No. 37

Test point 1	CAN gateway 16P connector (female terminal) No. 11:
Test point 2	PCM connector A (50P) No. 36

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN A_H wire and the F-CAN A_L wire are OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .

Repair an open in the F-CAN A_H wire or the F-CAN A_L wire between the PCM (A36, A37) and the CAN gateway.

Open wire check (F-CAN B_H line, F-CAN B_L line) 1

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. Jump the SCS line with the HDS, and wait more than 1 minute.

-3. Disconnect the following connectors.

CAN gateway 16P connector

PCM connector A (50P)

-4. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	PCM connector A (50P): disconnected
Test point 1	CAN gateway 16P connector (female terminal) No. 6:
Test point 2	PCM connector A (50P) No. 39

Test point 1	CAN gateway 16P connector (female terminal) No. 14:
Test point 2	PCM connector A (50P) No. 38

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN B_H wire and the F-CAN B_L wire are OK. Check for poor connections or loose terminals at the CAN gateway and the PCM. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good PCM .

Repair an open in the F-CAN B_H wire or the F-CAN B_L wire between the PCM (A38, A39) and the CAN gateway.

F-CAN circuit communication check (Transmitting control unit)

-1. Select the Function Test in the CAN Gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

F-CAN Bus Connected Unit Check

According to the detected DTC on the following table, make sure that the transmitting control unit detects the CAN gateway Bus channel (s) normally.

DTC	Transmitting control unit	Detected CAN getaway Bus channel (s) at normal
U0101	TCM	A
U0104	Millimeter wave radar	D
U0122	VSA modulator-control unit	A, B
U0128	VSA modulator-control unit (electric parking brake control unit)	A, B
U0129	Electric brake booster	A, B
U0131	EPS control unit	B
U0132	Adaptive damper control unit	B

DTC	Transmitting control unit	Detected CAN getaway Bus channel (s) at normal
U0151	SRS unit	B
U0155	Gauge control module	C
U129E	Body control module	A

Is it detected normally?

Detected normal

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the transmitting control unit and the CAN gateway.

U0101: TCM is Not Available for Bus A

Go to step 6.

U0104: Millimeter wave radar is Not Available for Bus D

Go to step 9.

U0122: VSA modulator-control unit is Not Available for Bus A

Go to step 6.

U0122: VSA modulator-control unit is Not Available for Bus B

Go to step 7.

U0128: VSA modulator-control unit (electric parking brake control unit) is Not Available for Bus A

Go to step 6.

U0128: VSA modulator-control unit (electric parking brake control unit) is Not Available for Bus B

Go to step 7.

U0129: Electric brake booster is Not Available for Bus A

Go to step 6.

U0129: Electric brake booster is Not Available for Bus B

Go to step 7.

U0131: EPS control unit connector is Not Available for Bus B

Go to step 7.

U0132: Adaptive damper control unit is Not Available for Bus B

Go to step 7.

U0151: SRS unit connector is Not Available for Bus B

Go to step 7.

U0155: Gauge control module is Not Available for Bus C

Go to step 8.

U129E: Body control module is Not Available for Bus A

Go to step 6.

Open wire check (F-CAN A_H line, F-CAN A_L line) 2

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

DTC	Connector
-	CAN gateway 16P connector

DTC	Connector
U0101	TCM 50P connector
U0122	VSA modulator-control unit 46P connector
U0128	VSA modulator-control unit 46P connector
U0129	Electric brake booster 26P connector
U129E	Body control module connector A (66P)

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	Transmitting control unit connector (s) for indicated DTCs: disconnected

DTC	Circuit name	Test point 1 (Receiving control unit)		Test point 2 (Transmitting control unit)
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0101	F-CAN A_H	CAN gateway 16P connector (female terminal) :	No. 3	TCM 50P connector	No. 3
U0101	F-CAN A_L	CAN gateway 16P connector (female terminal) :	No. 11	TCM 50P connector	No. 11
U0122	F-CAN A_H	CAN gateway 16P connector (female terminal) :	No. 3	VSA modulator-control unit 46P connector	No. 20
U0122	F-CAN A_L	CAN gateway 16P connector (female terminal) :	No. 11	VSA modulator-control unit 46P connector	No. 21
U0128	F-CAN A_H	CAN gateway 16P connector (female terminal) :	No. 3	VSA modulator-control unit 46P connector	No. 20
U0128	F-CAN A_L	CAN gateway 16P connector (female terminal) :	No. 11	VSA modulator-control unit 46P connector	No. 21
U0129	F-CAN A_H	CAN gateway 16P connector (female terminal) :	No. 3	Electric brake booster 26P connector	No. 26
U0129	F-CAN A_L	CAN gateway 16P connector (female terminal) :	No. 11	Electric brake booster 26P connector	No. 18
U129E	F-CAN A_H	CAN gateway 16P connector (female terminal) :	No. 3	Body control module connector A (66P)	No. 64
U129E	F-CAN A_L	CAN gateway 16P connector (female terminal) :	No. 11	Body control module connector A (66P)	No. 63

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN A_H wire and the F-CAN A_L wire are OK.

According to the detected DTC on the following table, update, substitute, or replace the correspond control unit.

DTC	Operation for transmitting control unit
U0101	Check for poor connections or loose terminals at the CAN gateway and the TCM. Substitute a known-good TCM .
U0122	Check for poor connections or loose terminals at the CAN gateway and the electric brake booster. Repalce the VSA modulator-control unit .
U0128	Check for poor connections or loose terminals at the CAN gateway and the electric brake booster. Replace the VSA modulator-control unit .
U0129	Check for poor connections or loose terminals at the CAN gateway and the electric brake booster. Replace the electric brake booster .
U129E	Check for poor connections or loose terminals at the CAN gateway and the body control module. Substitute a known-good body control module .

Repair an open in the F-CAN A_H wire or the F-CAN A_L wire between the transmitting control unit and the CAN gateway.

Open wire check (F-CAN B_H line, F-CAN B_L line) 2

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

DTC	Connector
-	CAN gateway 16P connector
U0122	VSA modulator-control unit 46P connector
U0128	VSA modulator-control unit 46P connector
U0129	Electric brake booster 26P connector
U0131	EPS control unit connector B (6P)
U0132	Adaptive damper control unit 24P connector
U0151	SRS unit connector A (43P)

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	Transmitting control unit connector (s) for indicated DTCs: disconnected

DTC	Circuit name	Test point 1 (Receiving control unit)		Test point 2 (Transmitting control unit)
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0122	F-CAN B_H	CAN gateway 16P connector (female terminal) :	No. 6	VSA modulator-control unit 46P connector	No. 24
U0122	F-CAN B_L	CAN gateway 16P connector (female terminal) :	No. 14	VSA modulator-control unit 46P connector	No. 25
U0128	F-CAN B_H	CAN gateway 16P connector (female terminal) :	No. 6	VSA modulator-control unit 46P connector	No. 24
U0128	F-CAN B_L	CAN gateway 16P connector (female terminal) :	No. 14	VSA modulator-control unit 46P connector	No. 25
U0129	F-CAN B_H	CAN gateway 16P connector (female terminal) :	No. 6	Electric brake booster 26P connector	No. 19
U0129	F-CAN B_L	CAN gateway 16P connector (female terminal) :	No. 14	Electric brake booster 26P connector	No. 12
U0131	F-CAN B_H	CAN gateway 16P connector (female terminal) :	No. 6	EPS control unit connector B (6P)	No. 4
U0131	F-CAN B_L	CAN gateway 16P connector (female terminal) :	No. 14	EPS control unit connector B (6P)	No. 1
U0132	F-CAN B_H	CAN gateway 16P connector (female terminal) :	No. 6	Adaptive damper control unit 24P connector	No. 19
U0132	F-CAN B_L	CAN gateway 16P connector (female terminal) :	No. 14	Adaptive damper control unit 24P connector	No. 20
U0151	F-CAN B_H	CAN gateway 16P connector (female terminal) :	No. 6	SRS unit connector A (43P)	No. 16
U0151	F-CAN B_L	CAN gateway 16P connector (female terminal) :	No. 14	SRS unit connector A (43P)	No. 17

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN B_H wire and the F-CAN B_L wire are OK.

According to the detected DTC on the following table, update, substitute, or replace the correspond control unit.

DTC	Operation for transmitting control unit
U0122	Check for poor connections or loose terminals at the CAN gateway and the VSA modulator-control unit. Replace the VSA modulator-control unit .
U0128	Check for poor connections or loose terminals at the CAN gateway and the VSA modulator-control unit. Replace the VSA modulator-control unit .

DTC	Operation for transmitting control unit
U0129	Check for poor connections or loose terminals at the CAN gateway and the electric brake booster. Replace the electric brake booster .
U0131	Check for poor connections or loose terminals at the CAN gateway and the EPS control unit. Substitute a known-good EPS control unit .
U0132	Check for poor connections or loose terminals at the CAN gateway and the adaptive damper control unit. Substitute a known-good adaptive damper control unit .
U0151	Check for poor connections or loose terminals at the CAN gateway and the SRS unit. Substitute a known-good SRS unit .

Repair an open in the F-CAN B_H wire or the F-CAN B_L wire between the transmitting control unit and the CAN gateway.

Open wire check (F-CAN C_H line, F-CAN C_L line)

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

DTC	Connector
-	CAN gateway 16P connector
U0155	Gauge control module connector A (32P)

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	Transmitting control unit connector (s) for indicated DTCs: disconnected

DTC	Circuit name	Test point 1 (Receiving control unit)		Test point 2 (Transmitting control unit)
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0155	F-CAN C_H	CAN gateway 16P connector (female terminal) :	No. 5	Gauge control module connector A (32P)	No. 20
U0155	F-CAN C_L	CAN gateway 16P connector (female terminal) :	No. 13	Gauge control module connector A (32P)	No. 21

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN C_H wire and the F-CAN C_L wire are OK.

According to the detected DTC on the following table, update, substitute, or replace the correspond control unit.

DTC	Operation for transmitting control unit
U0155	Check for poor connections or loose terminals at the CAN gateway and the gauge control module. Substitute a known-good gauge control module .

Repair an open in the F-CAN C_H wire or the F-CAN C_L wire between the transmitting control unit and the CAN gateway.

Open wire check (F-CAN D_H line, F-CAN D_L line)

-1. Turn the vehicle to the OFF (LOCK) mode.

-2. According to the detected DTC on the following table, disconnect the transmitting control unit connector (s).

DTC	Connector
-	CAN gateway 16P connector
U0104	Millimeter wave radar 8P connector

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	Transmitting control unit connector (s) for indicated DTCs: disconnected

DTC	Circuit name	Test point 1 (Receiving control unit)		Test point 2 (Transmitting control unit)
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0104	F-CAN D_H	CAN gateway 16P connector (female terminal) :	No. 7	Millimeter wave rader 8P connector	No. 7
U0104	F-CAN D_L	CAN gateway 16P connector (female terminal) :	No. 15	Millimeter wave rader 8P connector	No. 6

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN D_H wire and the F-CAN D_L wire are OK.

According to the detected DTC on the following table, update, substitute, or replace the correspond control unit.

DTC	Operation for transmitting control unit
U0104	Check for poor connections or loose terminals at the CAN gateway and the millimeter wave radar. Substitute a known-good millimeter wave radar .

Repair an open in the F-CAN D_H wire or the F-CAN D_L wire between the transmitting control unit and the CAN gateway.