DTC U0126-00: CAN Communication Failure With Absolute Steering Wheel Angle Sensor

NOTE:

Troubleshoot any PGM-FI DTCs first - Refer to: How to Troubleshoot the Fuel and Emissions Systems How to Troubleshoot the CVT System(CVT System) .
Before you troubleshoot, review the general troubleshooting information .

DTC Description	DTC	Freeze Frame
U0126-00 CAN Communication Failure With Absolute Steering Wheel Angle Sensor

1. DTC check:

1. Turn the vehicle to the ON mode.

2. Clear the DTC with the HDS.

3. Turn the vehicle to the OFF (LOCK) mode, then start the engine.

4. Check for DTCs with the HDS.

DTC Description	DTC	Freeze Frame
U0029-00 CAN Communication Failure (Bus OFF)
U0126-00 CAN Communication Failure With Absolute Steering Wheel Angle Sensor

Is DTC U0126-00 indicated?

YES

If only DTC U0126-00 is indicated, go to step 2.

YES

If DTC U0029-00 is also indicated, go to DTC U0029-00 .

Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting . If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the Freeze data/on-board snapshot.

2. Open wire check (F-CAN_H, F-CAN_L lines):

1. Turn the vehicle to the OFF (LOCK) mode.

2. Disconnect the following connectors.

VSA modulator-control unit 38P connector

Steering angle sensor 4P connector

3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	VSA modulator-control unit 38P connector: disconnected
	Steering angle sensor 4P connector: disconnected
Test circuit 1
Test point 1	VSA modulator-control unit 38P connector No. 38
Test point 2	Steering angle sensor 4P connector No. 2

Test circuit 2
Test point 1	VSA modulator-control unit 38P connector No. 26
Test point 2	Steering angle sensor 4P connector No. 3

Courtesy of HONDA, U.S.A., INC.

Is there continuity?

YES

The F-CAN_H and F-CAN_L wires are OK. Go to step 3.

Repair an open in the wire between the VSA modulator-control unit and the steering angle sensor.

3. Open wire check (IG1 ABS/VSA line):

1. Turn the vehicle to the ON mode.

2. Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	VSA modulator-control unit 38P connector: disconnected
	Steering angle sensor 4P connector: disconnected
Test point 1	Steering angle sensor 4P connector No. 1
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Is there battery voltage?

YES

The IG1 ABS/VSA wire is OK. Go to step 4.

Repair an open in the wire between the No. B24 (7.5 A) fuse in the under-dash fuse/relay box and the steering angle sensor.

4. Open wire check (GND line):

1. Turn the vehicle to the OFF (LOCK) mode.

2. Reconnect the following connectors.

VSA modulator-control unit 38P connector

Steering angle sensor 4P connector

3. Turn the vehicle to the ON mode.

4. Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
Test point 1	Steering angle sensor 4P connector No. 4
Test point 2	Body ground

Courtesy of HONDA, U.S.A., INC.

Is there 0.1 V or less?

YES

The GND wire is OK. Go to step 5.

Repair an open in the wire between the steering angle sensor and body ground (G501).

5. Steering angle sensor check (substitution):

1. Turn the vehicle to the OFF (LOCK) mode.

2. Substitute a known-good steering angle sensor .

3. Turn the vehicle to the ON mode.

4. Clear the DTC with the HDS.

5. Turn the vehicle to the OFF (LOCK) mode, then start the engine.

6. Check for DTCs with the HDS.

DTC Description	DTC	Freeze Frame
U0126-00 CAN Communication Failure With Absolute Steering Wheel Angle Sensor

Is DTC U0126-00 indicated?

YES

Go to step 6.

Replace the original steering angle sensor .

6. VSA modulator-control unit check (update):
1. Update the VSA modulator-control unit if it does not have the latest software .

2. Turn the vehicle to the OFF (LOCK) mode, then start the engine.

3. Check for DTCs with the HDS.

Is DTC U0126-00 indicated?

YES

Check for loose terminals and poor connections in the VSA modulator-control unit 38P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit .

NO

Troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCs troubleshooting.