DTC U128F: Gauge Control Module Lost Communication With BSI Control Unit (BSI message)

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0), and then back to ON (II).
Wait for at least 6 seconds.
Check for DTCs with the HDS.
Is DTC U128F indicated?

YES -Go to step 5.

NO -Intermittent failure, the system is OK at this time. Check for loose or poor connections between the gauge control module and the BSI control unit.
From the BODY ELECTRICAL SYSTEM SELECT menu, select B-CAN CONTROL UNITS INFORMATION, and then select CHECK CONNECTED CONTROL UNITS.
Is the BSI control unit detected?

YES -Go to step 10.

NO -Go to step 6.
Measure the voltage between body ground and BSI control unit 16P connector terminals No. 15.

Fig 1: Measuring Voltage Between Body Ground And BSI Control Unit 16P Connector Terminals No. 15
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 9.

NO -Go to step 7.
Turn the ignition switch to LOCK (0).
Check the No. E13 (7.5 A) fuse in the rear fuse box.
Is the fuse OK?

YES -Go to step 8.

NO -Replace the fuse. If the fuse blows again, repair a short to ground on the No. E13 (7.5 A) fuse circuit.
Measure the voltage between body ground and BSI control unit 16P connector terminal No. 2.

Fig 2: Measuring Voltage Between Body Ground And BSI Control Unit 16P Connector Terminal No. 2
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 0.2V

YES -Go to step 10.

NO -Repair an open or high resistance in the ground wire or poor ground (G801).
Turn the ignition switch to LOCK (0).
Disconnect the BSI control unit 16P connector.
Disconnect gauge control module 32P connector.
Check for continuity between BSI control unit 16P connector terminal No. 3 and No. 4 and gauge control module 32P connector terminal No. 29 and No. 30 respectively.

Fig 3: Checking Continuity Between BSI Control Unit 16P Connector Terminal And Gauge Control Module 32P Connector Terminal
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Replace the BSI control unit (see BSI RADAR UNIT REMOVAL/INSTALLATION ).

NO -Repair an open or poor connection in the B-CAN wire between the gauge control module and the BSI control unit.