Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks (2021 2022 2023 2024 2025)

Check the PCM for DTCs and troubleshoot PCM or F-CAN loss of communication errors first, then do this diagnosis if the symptom is related to the B-CAN system.

1. Compare the symptom with this list of B-CAN related systems:

• Gauge control module
• Exterior lights
• Turn signals
• Entry light control
• Interior lights
• Safety indicators
• Horns (security and panic) (if equipped)
• Reminder chimes (seat belt, lights-on, and parking brake)
• Power window/moonroof timer (if equipped)
• Wiper/washer
• Security (if equipped)
• Keyless entry
• Key interlock
• Power door locks
• Dashlights brightness
• Immobilizer
• Daytime running lights
• Driving position memory system
• Keyless access control
• Climate control
• BSI system
• Seat heater

• -

  If the symptom is related to the B-CAN, go to step 2.

• -

  If the symptom is not related to the B-CAN, go to the system symptom troubleshooting.

2. Connect the HDS to the data link connector (DLC) .

3. From the BODY ELECTRICAL system, select Mode Menu, then select the Connected Unit Menu to see if the following control units are communicating with the HDS.

• MICU
• Climate control unit
• Automatic lighting/rain sensor (with automatic wiper)
• Automatic lighting control unit-sensor (without automatic wiper)
• Keyless access/TPMS control unit
• Door multiplex control unit
• Power seat control unit
• Parking and back-up sensor control unit
• Left side BSI radar unit
• Right side BSI radar unit
• Ventilated seat control unit (with ventilated seat)
• Front seat heater control unit (without ventilated seat)
• Rear seat heater control unit
• Wireless charger

NOTE: 

• If a unit is communicating with the HDS, "DETECT" is displayed.
• If a unit is not communicating or the vehicle is not equipped, "NOT AVAILABLE" is displayed.
• The HDS only checks the status one time when BODY ELECTRICAL is selected. To recheck the status after repair, reboot the HDS.

1. -

   If all control units are communicating with the HDS, go to step 4.

2. -

   If any of the control units are not communicating, go to B-CAN System Diagnosis Test Mode B .

3. -

   If all units are not communicating or only the MICU is communicating, go to MICU DTC U1280 troubleshooting .

4. Select the system that has the problem from the BODY ELECTRICAL SYSTEM SELECT menu, then select DTCs.

1. -

   If any DTCs are indicated, go to step 5.

5. Record all DTCs, and sort them by DTC type, then troubleshoot them in this order:

• Internal error DTCs.
• Loss of communication DTCs.
• Signal error DTCs.