DTC U1296: Gauge Control module Lost Communication With HVAC Display Unit

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 U1296 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 climate control unit.
From the BODY ELECTRICAL SYSTEM SELECT menu, select B-CAN CONTROL UNITS INFORMATION, and then select CHECK CONNECTED CONTROL UNITS.
Is the climate control unit or HVAC control unit detected?

YES -Go to step 11.

NO -Go to step 6.
Measure the voltage between body ground and climate control unit connector A (28P) or HVAC control unit 28P connector terminal No. 1.

Fig 1: Measuring Voltage Between Body Ground And Climate Control Unit Connector A (28P) Or HVAC Control Unit 28P Connector Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -
- With climate control: Go to step 7.
- Without climate control: Go to step 10.
Go to step 7.

NO -Go to step 8.
Measure the voltage between climate control unit connector B (16P) terminals No. 16 and body ground.

Fig 2: Measuring Voltage Between Climate Control Unit Connector B (16P) Terminals No. 16 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?

YES -Go to step 10.

NO -Go to step 8.
Turn the ignition switch to LOCK (0).
Check the No. B16 (10 A) fuse in the under-hood fuse/relay box and the No. C26 (7.5 A) fuse in the driver's under-dash fuse/relay box.
Are the fuses OK?

YES -Repair an open or high resistance in the No. B16 (10 A) and/or No. C26 (7.5 A) fuse circuit.

NO -Replace the fuse(s). If the fuse blows again, repair a short to ground in the No. B16 (10 A) and/or No. C26 (7.5 A) fuse circuit.
Measure the voltage between body ground and climate control unit connector A (28P) or HVAC control unit 28P connector terminal No. 12.

Fig 3: Measuring Voltage Between Body Ground And Climate Control Unit Connector A (28P) Or HVAC Control Unit 28P Connector Terminal No. 12
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there less than 0.2V

YES -Go to step 11.

NO -Repair an open or high resistance in the ground wire or poor ground (G403).
Turn the ignition switch to LOCK (0).
Disconnect these items:
- Gauge control module 32P connector.
- Climate control unit connector A (28P) 1
- HVAC control unit 28P connector 2
1. With climate control
2. Without climate control
Check for continuity between gauge control module connector (32P) terminal No. 29 and No. 30 and climate control unit connector A (28P) or HVAC control unit 28P connector terminal No. 26 and No. 28 respectively.

Fig 4: Checking Continuity Between Gauge Control Module Connector Terminal And Climate Control Unit Connector Terminal
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Replace the climate control unit (see SUNLIGHT SENSOR REPLACEMENT ) or HVAC control unit (see HVAC CONTROL UNIT REMOVAL/INSTALLATION ).

NO -Repair an open or poor connection in the B-CAN wire(s) between the gauge control module and the climate control unit or HVAC control unit.