DTC Troubleshooting: U1281, U1288

DTC U1281: Gauge Control Module Lost Communication with MICU (Body Control Module) (MICU Frame)
DTC U1288: Gauge Control Module Lost Communication with PARKSR

NOTE:

	If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.
	According to the detected DTC(s), check for the power circuit and the ground circuit of the control unit which cannot communicate with the gauge control module.
	Refer to the DTC shown on the display, then inspect the connectors and terminals based on the instructions.

DTC Description	DTC
U1281 Gauge Control Module Lost Communication with MICU (Body Control Module) (MICU Frame)
U1288 Gauge Control Module Lost Communication with PARKSR

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 and then the ON mode.

?4.	Wait for at least 6 seconds.

?5.

Check for DTCs with the HDS.

DTC Description	DTC
U1281 Gauge Control Module Lost Communication with MICU (Body Control Module) (MICU Frame)
U1288 Gauge Control Module Lost Communication with PARKSR

Are any DTCs indicated?


	YES

Go to step 2.


	NO

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals between the body control module and the gauge control module.?

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

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

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

?2.

Disconnect the receiving control unit connector.

Gauge control module connector A (32P)

?3.

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

DTC	Connector
U1281	Body control module connector B (36P)
U1288	Parking and back-up sensor control unit 16P connector

?4.

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

Test condition

Vehicle OFF (LOCK) mode
Gauge control module connector A (32P): 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
U1281	B-CAN_H	Gauge control module connector A (32P)	No. 30	Body control module connector B (36P)	No. 20
U1281	B-CAN_L	Gauge control module connector A (32P)	No. 31	Body control module connector B (36P)	No. 21
U1288	B-CAN_H	Gauge control module connector A (32P)	No. 30	Parking and back-up sensor control unit 16P connector	No. 9
U1288	B-CAN_L	Gauge control module connector A (32P)	No. 31	Parking and back-up sensor control unit 16P connector	No. 2

Is there 1.0 ? or less?


	YES

The B-CAN_H wire and the B-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
U1281	Substitute a known-good body control module, then recheck. If DTC U1281 goes away after substitution, replace the original body control module.
U1288	Substitute a known-good parking and back-up sensor control unit, then recheck. If DTC U1288 goes away after substitution, replace the original parking and back-up sensor control unit.


	NO

Repair an open in the B-CAN_H wire and/or the B-CAN_L wire between the gauge control module and the transmitting control unit.?