DTC U128D: Door Multiplex Control Unit Lost Communication With Gauge Control Module (2016-18)

DTC (Door Multiplex Control Unit)

1. Problem verification:

   Clear the DTCs with the HDS.

   Clear DTCs

   - 2. Press the engine start/stop button to select the OFF mode and then the ON mode.

   - 3. Wait for at least 6 seconds.

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC
   U128D Door Multiplex Control Unit Lost Communication With Gauge Control Module

   Is DTC U128D indicated?

   YES 

   Go to step 2.

   NO 

   Intermittent failure, the system is OK at this time. Check for loose or poor connections.

2. Determine possible failure area (gauge control module power and ground, B CAN line):

   Select GAUGES from the BODY ELECTRICAL SYSTEM SELECT menu, and then select DATA LIST.

   Does the DATA LIST appear?

   YES 

   Go to step 5.

   NO 

   Go to step 3.

3. Fuse check:

   Check the following fuse.

   Fuse	No. A29 (10 A)
   Location	Under-hood fuse/relay box

   Is the fuse OK?

   YES 

   Go to step 4.

   NO 

   Replace the fuse. If the fuse blows again, repair a short to ground in the No. A29 (10 A) fuse circuit.

4. Open wire check (+B BACK UP line):

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

   - 2. Disconnect the following connector.

   Gauge control module 32P connector

   - 3. Measure the voltage between test points 1 and 2.

   Test condition	OFF modeGauge control module 32P connector: disconnected
   Test circuit	+B BACK UP
   Test point 1	Gauge control module 32P connector No. 1 (GRN)
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   Repair an open or high resistance in the ground wire or poor ground (G502).

   NO 

   Repair an open or high resistance in the wire.

5. Open wire check (B CAN-H line):

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

   - 2. Disconnect the following connector.

   Gauge control module 32P connector

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

   Without color multi-information display (MID) 

   Test condition	OFF modePower window master switch 37P connector: disconnectedGauge control module 32P connector: disconnected
   Test circuit	B CAN-H
   Test point 1	Power window master switch 37P connector No. 28 (PNK)
   Test point 2	Gauge control module 32P connector No. 7 (PNK)

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

   With color multi-information display (MID) 

   Test condition	OFF modePower window master switch 37P connector: disconnectedGauge control module 32P connector: disconnected
   Test circuit	B CAN-H
   Test point 1	Power window master switch 37P connector No. 28 (PNK)

   Test point 2

   Gauge control module 32P connector No. 25 (PNK)

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

   Is there continuity?

   YES 

   The B CAN-H wire is OK. Go to step 6.

   NO 

   An open or poor connection in the B CAN-H wire between the power window master switch and the gauge control module.

6. Open wire check (B CAN-L line):

   Check for continuity between test points 1 and 2.

   Without color multi-information display (MID) 

   Test condition	OFF modePower window master switch 37P connector: disconnectedGauge control module 32P connector: disconnected
   Test circuit	B CAN-L
   Test point 1	Power window master switch 37P connector No. 30 (BLU)
   Test point 2	Gauge control module 32P connector No. 8 (BLU)

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

   With color multi-information display (MID) 

   Test condition	OFF modePower window master switch 37P connector: disconnectedGauge control module 32P connector: disconnected
   Test circuit	B CAN-L
   Test point 1	Power window master switch 37P connector No. 30 (BLU)
   Test point 2	Gauge control module 32P connector No. 26 (BLU)

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

   Is there continuity?

   YES 

   The B CAN-L wire is OK. Replace the power window master switch .

   NO 

   An open or poor connection in the B CAN-L wire between the power window master switch and the gauge control module.