Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Troubleshooting - B-CAN System Diagnosis Test Mode A
Check the PCM for DTCs and troubleshoot PCM or F-CAN loss of communication errors first (see GENERAL TROUBLESHOOTING INFORMATION ), then perform this diagnosis first if the symptom is related to the B-CAN system.
- Compare the system with this list of B-CAN related systems:
- Gauge control module
- Exterior lights
- Turn signals
- Entry light control
- Interior lights
- Safety indicators
- Rear window defogger
- Horns (security and panic)
- Chimes (key, seat belt, lights-on, and parking brake)
- Power windows
- Power window/moonroof timer
- Wiper/washer
- Security
- Keyless entry
- Power door locks
- Climate control
- Key interlock
- Dash light brightness
- Driving position memory
- Power tailgate
- Power sliding doors
- Compass
Is the symptom related to the B-CAN system?
- YES - Go to step 2.
- NO - Go to the system troubleshooting for the system with the symptom.
- Connect the Honda Diagnosis System (HDS), then turn the ignition switch ON (II).
- From the BODY ELECTRICAL SYSTEM SELECTION MENU, select UNIT INFORMATION, and then select CONNECTED UNIT listed to see if the following control units are communicating with the HDS.
- MICU
- Door multiplex control unit
- Gauge control module
- Combination switch control unit
- Relay control module
- MICU-rear junction box
- Power seat control unit
- Power tailgate control unit
- Left power sliding door control unit
- Right power sliding door control unit
- A/C control panel/climate control unit
- Automatic lighting control unit
NOTE:- If one or more of the units are communicating with the HDS, DETECT will be displayed.
- If the unit is not communicating or the vehicle is not equipped, "Not Available" will be displayed.
Are all control units communicating with the HDS?
- YES - Go to step 4.
- NO - If any of the control units are not communicating, go to B-CAN System Diagnosis Test Mode B (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE B ). If all units are not communicating or only the MICU is communicating, go to DTC B1000 troubleshooting (see DTC TROUBLESHOOTING ).
- Select the system that has the problem from the BODY ELECTRICAL SYSTEM SELECTION MENU, then select DTCs.
Are any DTCs indicated?
- YES - Go to step 5.
- NO - If the problem is related to one of the following items, go to B-CAN System Diagnosis Test Mode C (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE C ).
- Exterior lights
- Turn signals
- Entry light control
- Interior lights
- Horns (security and panic)
- Power windows
- Wiper/washer
- Power tailgate
- Power sliding door
- Compass
If the problem is related to one of the following items, go to the troubleshooting for that individual system.
- Gauge control module
- Safety indicators
- Chimes (key, seat belt and lights-on)
- Rear window defogger (climate control)
- Security
- Keyless entry
- Climate control
- Key interlock
- Dash light brightness
- Audio system
- Navigation
- Driving position memory
- Power tailgate
- Power sliding door
- Compass
- Record all DTCs, and sort them by DTC type.
- Troubleshoot the DTC(s) in this order:
- Battery voltage DTCs.
- Internal error DTCs.
- Loss of communication DTCs. Begin troubleshooting with the lowest number first (Example: if DTCs B1006 and B1058 are retrieved, begin by troubleshooting B1006).
- Signal error DTCs.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.