Honda HR-V Owners & Service Manuals

Honda HR-V: DTC Troubleshooting 51-12: Motor Power Source Circuit Malfunction

Honda HR-V (2015-2021) Service Manual / Brakes / VSA System - Diagnostics / DTC Troubleshooting / DTC Troubleshooting 51-12: Motor Power Source Circuit Malfunction

NOTE: Before you troubleshoot, review the general troubleshooting information.

VSA System - Diagnostics

1. Problem verification:

  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 to the ON mode.
  4. Check for DTCs with the HDS.

VSA System - Diagnostics

Is DTC 51-12 indicated?

YES

The failure is duplicated. Go to step 2.

NO

Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.

2. Fuse check:

  1. Turn the vehicle to the OFF (LOCK) mode.
  2. Check the following fuse.

VSA System - Diagnostics

Is the fuse OK?

YES

The fuse is OK. Reinstall the fuse, then go to step 5.

NO

Go to step 3.

3. Shorted wire check (+B ABS/VSA MTR line):

  1. Disconnect the following connector.

VSA modulator-control unit 21P connector

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

VSA System - Diagnostics

Is there continuity?

YES

Repair a short to body ground in the +B ABS/VSA MTR wire between the No. D1-4 (40 A) fuse in the auxiliary under-dash fuse box A and the VSA modulator-control unit.

NO

The +B ABS/VSA MTR wire is OK. Install a new No. D1-4 (40 A) fuse in the auxiliary under-dash fuse box A, then go to step 4.

4. VSA modulator-control unit check:

  1. Reconnect the following connector.

VSA modulator-control unit 21P connector

  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 to the ON mode.
  4. Check for DTCs with the HDS.

VSA System - Diagnostics

Is DTC 51-12 indicated?

YES

Go to step 5.

NO

The troubleshooting is complete.

5. Open wire check (+B ABS/VSA MTR line):

  1. Turn the vehicle to the OFF (LOCK) mode.
  2. Disconnect the following connector.

VSA modulator-control unit 21P connector

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

VSA System - Diagnostics

Is there battery voltage?

YES

The +B ABS/VSA MTR wire is OK. Go to step 6.

NO

Repair an open in the +B ABS/VSA MTR wire between the No. D1-4 (40 A) fuse in the auxiliary under-dash fuse box A and the VSA modulator-control unit.

6. VSA modulator-control unit check (update):

  1. Reconnect the following connector.

VSA modulator-control unit 21P connector (if disconnected)

  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 to the ON mode.
  3. Check for DTCs with the HDS.

VSA System - Diagnostics

Is DTC 51-12 indicated?

YES

Check for loose terminals in the VSA modulator-control unit 21P 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.

    READ NEXT:

     DTC Troubleshooting 52-11: Motor Stuck OFF

    NOTE: Before you troubleshoot, review the general troubleshooting information. DTCs (VSA) 1. Solenoid operation check: Turn the vehicle to the ON mode. Clear the DTC with the HDS. Turn the vehic

     DTC Troubleshooting 53-11: Motor Relay Stuck ON

    NOTE: Before you troubleshoot, review the general troubleshooting information. 1. Problem verification: Turn the vehicle to the ON mode. Clear the DTC with the HDS. Turn the vehicle to the OFF (

     DTC Troubleshooting 54-11, 54-12: Fail-Safe Relay Stuck

    NOTE: Before you troubleshoot, review the general troubleshooting information. 1. Problem verification: Turn the vehicle to the ON mode. Clear the DTC with the HDS. Turn the vehicle to the OFF (

    SEE MORE:

     A Few Words About Safety

    Service Information The service and repair information contained in this manual is intended for use by qualified, professional technicians. Attempting service or repairs without the proper training, tools, and equipment could cause injury to you or others. It could also damage the vehicle or crea

     Testing

    MOONROOF MOTOR-CONTROL UNIT INPUT TEST NOTE : Testing Before testing, make sure the No. C18 (20 A) and No. C39 (7.5 A) fuses in the under-dash fuse/relay box are OK. If the moonroof works OK manually, but will not work in AUTO, or reverses frequently (obstacle detection), reset the moonroof

    © 2019-2025 Copyright www.hohrv2.com