DTC U128F (Gauge Control Module (With Auto Idle Stop System)) (2016)

DTC U128F  : Gauge control module lost communication with BSI unit

DTC (Gauge Control Module)

1. Problem verification

   - 1. Clear the DTCs with the HDS.

   - 2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

   - 3. Wait for at least 6 seconds.

   - 4. Check for DTCs with the HDS.

   DTC Description	DTC
   U128F Gauge control module lost communication with BSI unit

   Is DTC U0128F 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 (BSI radar unit power and ground, B CAN line)

   - 1. Select B-CAN CONTROL UNITS INFORMATION from the BODY ELECTRICAL SYSTEM SELECT menu, and then select CHECK CONNECTED CONTROL UNITS.

   - 2. Check the DETECT/NOT AVAILABLE information of the BSI RADAR UNIT

   Is DETECT indicated?

   YES 

   Go to step 8.

   NO 

   Go to step 3.

3. Fuse check

   - 1. Check the following fuses.

   Fuse	No. D24 (7.5 A)
   Location	Driver's under-dash fuse/relay box

   Fuse	No. H7 (10 A)
   Location	Auxiliary under-dash fuse/relay box

   Is each fuse OK?

   YES 

   Go to step 4.

   NO 

   Replace the fuse. If the fuse blows again, repair a short to ground in the No. D24 (7.5 A) and/or No. H7 (10 A) fuse circuit (s).

4. Relay check

   - 1. Check the following relay.

   Relay	DC-DC converter IG1 relay1
   Location	Auxiliary under-dash fuse/relay box

   Is relay OK?

   YES 

   Go to step 5.

   NO 

   Replace the DC-DC converter IG1 relay1.

5. Open wire check (IG1 METER (DC/DC) line)

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

   - 2. Disconnect the following connector.

   Left side BSI radar unit 6P connector - Refer to: BSI Radar Unit Removal and Installation (2016 2017 2018 2019 2020)

   - 3. Turn the vehicle to the ON mode.

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

   Test condition	Vehicle ON mode Left side BSI radar unit 6P connector: disconnected
   Test circuit	IG1 METER (DC/DC)
   Test point 1	Left side BSI radar unit 6P connector No. 1 (GRN)
   Test point 2	Body ground

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

   Is there battery voltage?

   YES 

   The IG1 METER (DC/DC) wire is OK. Go to step 6.

   NO 

   Repair an open or high resistance in the wire.

6. Open wire check (SGND line)

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

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

   Test condition	Vehicle OFF (LOCK) mode Left side BSI radar unit 6P connector: disconnected
   Test circuit	SGND
   Test point 1	Left side BSI radar unit 6P connector No. 6 (BLK)
   Test point 2	Body ground

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

   Is there continuity?

   YES 

   The SGND wire is OK. Go to step 7.

   NO 

   Repair an open or high resistance in the ground wire or poor ground (G605).

7. Open wire check (B-CAN lines)

   - 1. Disconnect the following connector.

   Gauge control module connector A (32P)

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

   Test condition	Vehicle OFF (LOCK) mode Left side BSI radar unit 6P connector: disconnected Gauge control module connector A (32P): disconnected
   Test circuit	B-CAN_H
   Test point 1	Left side BSI radar unit 6P connector No. 3 (PNK)
   Test point 2	Gauge control module connector A (32P) No. 25 (PNK)

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

   Is there continuity?

   YES 

   An open or poor connection in the B-CAN_L wire between the left side BSI radar unit and the gauge control module.

   NO 

   An open or poor connection in the B-CAN_H wire between the left side BSI radar unit and the gauge control module.

8. Open wire check (B-CAN lines)

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

   - 2. Disconnect the following connector.

   Left side BSI radar unit 6P connector - Refer to: BSI Radar Unit Removal and Installation (2016 2017 2018 2019 2020)

   Gauge control module connector A (32P)

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

   Test condition	Vehicle OFF (LOCK) mode Left side BSI radar unit 6P connector: disconnected Gauge control module connector A (32P): disconnected
   Test circuit	B-CAN_H
   Test point 1	Left side BSI radar unit 6P connector No. 3 (PNK)
   Test point 2	Gauge control module connector A (32P) No. 25 (PNK)

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

   Is there continuity?

   YES 

   An open or poor connection in the B-CAN_L wire between the left side BSI radar unit and the gauge control module.

   NO 

   An open or poor connection in the B-CAN_H wire between the left side BSI radar unit and the gauge control module.