DTC Troubleshooting: U0122, U0128, U0131, U0151, U0155, U129E (K20C1: Without CAN gateway)

DTC Troubleshooting: U0122, U0128, U0131, U0151, U0155, U129E

DTC U0122: F-CAN Malfunction (PCM-VSA Modulator-Control Unit)
DTC U0128: F-CAN Malfunction (PCM-Electric Parking Brake Control Unit)
DTC U0131: F-CAN Malfunction (PCM-EPS 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, do the 12 volt battery terminal disconnection procedure, and wait for at least 3 minutes.
	Refer to the DTC shown on the display, then inspect the connectors and terminals based on the instructions.

DTC Description	Confirmed DTC	Pending DTC
U0122 F-CAN Malfunction (PCM-VSA Modulator-Control Unit)
U0128 F-CAN Malfunction (PCM-Electric Parking Brake Control Unit)
U0131 F-CAN Malfunction (PCM-EPS 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))

Problem verification:

Problem verification

?1.	Turn the vehicle to the ON mode.

?2.	Clear the DTC with the HDS.

?3.	Turn the vehicle to the OFF (LOCK) mode.

?4.	Turn the vehicle to the ON mode.

?5.

Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC
U0122 F-CAN Malfunction (PCM-VSA Modulator-Control Unit)
U0128 F-CAN Malfunction (PCM-Electric Parking Brake Control Unit)
U0131 F-CAN Malfunction (PCM-EPS 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))

Are any DTCs 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 the transmitting control units and the PCM. If the on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the on-board snapshot.?

Open wire check (F-CAN_H line, F-CAN_L line):

Open wire check (F-CAN_H line, F-CAN_L line)

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

?2.

Disconnect the receiving control unit connector(s).

NOTE: Jump the SCS line with the HDS, and wait more than 1 minute when removing the PCM connector(s).

PCM connector No. 2 (58P)

?3.

Disconnect the transmitting control unit connector(s).

Refer to the DTC shown on the display, then disconnect the connector(s) based on the instructions (see table).

DTC	Connector
U0122	VSA modulator-control unit 46P connector
U0128	VSA modulator-control unit 46P connector
U0131	EPS control unit connector B (6P)
U0151	SRS unit connector A (39P)
U0155	Gauge control module connector A (32P)
U129E	Body control module connector B (36P)

?4.

Check for continuity between the receiving control unit and the transmitting control unit on the F-CAN_H circuit and the F-CAN_L circuit.

Test condition	Vehicle OFF (LOCK) mode
	Receiving control unit connector(s): disconnected
	Transmitting control unit connector(s) for indicated DTCs: disconnected

DTC	Circuit name	Receiving control unit		Transmitting control unit
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0122	F-CAN_H	PCM connector No. 2 (58P)	No. 15	VSA modulator-control unit 46P connector	No. 20
U0122	F-CAN_L	PCM connector No. 2 (58P)	No. 27	VSA modulator-control unit 46P connector	No. 21
U0128	F-CAN_H	PCM connector No. 2 (58P)	No. 15	VSA modulator-control unit 46P connector	No. 20
U0128	F-CAN_L	PCM connector No. 2 (58P)	No. 27	VSA modulator-control unit 46P connector	No. 21
U0131	F-CAN_H	PCM connector No. 2 (58P)	No. 15	EPS control unit connector B (6P)	No. 3
U0131	F-CAN_L	PCM connector No. 2 (58P)	No. 27	EPS control unit connector B (6P)	No. 1
U0151	F-CAN_H	PCM connector No. 2 (58P)	No. 15	SRS unit connector A (39P)	No. 34
U0151	F-CAN_L	PCM connector No. 2 (58P)	No. 27	SRS unit connector A (39P)	No. 35
U0155	F-CAN_H	PCM connector No. 2 (58P)	No. 15	Gauge control module connector A (32P)	No. 19
U0155	F-CAN_L	PCM connector No. 2 (58P)	No. 27	Gauge control module connector A (32P)	No. 20
U129E	F-CAN_H	PCM connector No. 2 (58P)	No. 15	Body control module connector B (36P)	No. 22
U129E	F-CAN_L	PCM connector No. 2 (58P)	No. 27	Body control module connector B (36P)	No. 23

Is there continuity?


	YES

The F-CAN_H wire and the F-CAN_L wire are OK.

Refer to the DTC shown on the display, then substitute or replace the control unit based on the instructions (see table).?

DTC	Operation for transmitting control unit
U0122	Replace the VSA modulator-control unit.
U0128	Replace the VSA modulator-control unit.
U0131	Replace the EPS control unit.
U0151	Substitute the SRS unit. If DTC U0151 goes away after substitution, replace the original SRS unit.
U0155	Substitute a known-good gauge control module, then recheck. If DTC U0155 goes away after substitution, replace the original gauge control module.
U129E	Substitute a known-good body control module, then recheck. If DTC U129E goes away after substitution, replace the original body control module.


	NO

Repair an open in the F-CAN_H wire and/or the F-CAN_L wire between the receiving control unit and the transmitting control unit.?