Honda HR-V: DTC U1280 (MICU) B-CAN Communication Bus Line Error (BUS-OFF)
.png)
DTC (MICU)
NOTE : If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A - Refer to: Body Electrical Troubleshooting - B-CAN System Diagnosis Test Mode A - Initial Communication and DTC Checks.
1. Problem verification:
- Clear the DTCs with the HDS.
Clear DTCs
- Turn the vehicle to the OFF (LOCK) mode and then the ON mode.
- Wait for at least 6 seconds.
- Check for DTCs with the HDS.
.png)
Is DTC U1280 indicated?
YES
Go to step 2.
NO
Intermittent failure, the system is OK at this time. Check for loose or poor connections.
2. B-CAN related units check:
- Turn the vehicle to the OFF (LOCK) mode.
- Disconnect the appropriate connector at each control unit in the table one at a time. Clear the DTC, then recheck for DTCs after each unit is disconnected.
.png)
Clear DTCs
.png)
Is DTC U1280 indicated with each individual unit disconnected?
YES
Leave the connectors disconnected, and go to step 3.
NO
Replace the control unit that was disconnected when DTC U1280 did not reset.
3. Shorted wire check (B-CAN lines) 1:
- Turn the vehicle to the OFF (LOCK) mode.
- Disconnect the following connectors.
Under-dash fuse/relay box connector D (24P) Under-dash fuse/relay box connector H (20P)
- Check for continuity between test points 1 and 2.
.png)
.png)
Is there continuity?
YES
Repair a short to ground in the B-CAN wires.
NO
Go to step 4.
4. Shorted wire check (B-CAN lines) 2:
- Check for continuity between test points 1 and 2.
.png)
Is there continuity?
YES
Repair a short to ground in the B-CAN wires.
NO
Go to step 5.
5. Shorted wire check (B-CAN_L to B-CAN_H line) 1:
- Check for continuity between test points 1 and 2.
.png)
Is there continuity?
YES
Repair a short in the B-CAN_L to B-CAN_H wire.
NO
Go to step 6.
6. Shorted wire check (B-CAN_L to B-CAN_H line) 2:
- Check for continuity between test points 1 and 2.
.png)
Is there continuity?
YES
Repair a short in the B-CAN_L to B-CAN_H wire.
NO
The B-CAN_L to B-CAN_H wire is OK. Faulty MICU; replace the under-dash fuse/relay box.
READ NEXT:
DTC U128D (MICU) MICU Lost Communication With Gauge Control Module
NOTE : The DTC may be stored due to the grounding failure or the power source
failure at the transmitting
control unit (the grounding inspection and the power source inspection on each
control unit
DTC B2A60-54 FCW/LDW Camera Unit/Multi Purpose Camera Unit Aiming
Incomplete
NOTE :
Before you troubleshoot, review the how to troubleshoot information -
Refer to: How to Troubleshoot
the Forward Collision Warning (FCW), or How to Troubleshoot the Lane
Departure Warning
SEE MORE:
Main & Connecting Rod Bearing Clearance
NOTE: Examples used in this article are general in nature and do not
necessarily relate
to a specific engine or system. Illustrations and procedures have been chosen
to guide mechanic through engine overhaul process. Descriptions of processes
of cleaning, inspection, assembly and machine shop pract
CVT System Description - Electronic Control System (CVT)
Functional Diagram
The electronic control system consists of the powertrain control module (PCM),
sensors, and solenoid valves. Shifting and lock-up are electronically controlled
for comfortable driving under all
conditions. The PCM receives input signals from the sensors and other control
units,
