VSA DTC 59-1 (2016)

DTC 59-1  : Brake Diag Circuit ON Failure

NOTE:  Before you troubleshoot, review the general troubleshooting information - Refer to:

How to Troubleshoot the VSA System (2014 2015 2016)

DTCs (VSA)

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. Wait 2 seconds or more without pressing the brake pedal.

   - 5. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   59-1 Brake Diag Circuit ON Failure

   Is DTC 59-1 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 - Refer to:

   How to Troubleshoot the VSA System (2014 2015 2016)

   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. Brake light relay check

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

   - 2. Check the brake lights without pressing the brake pedal.

   Are the brake lights on?

   YES 

   Replace the brake light relay.

   NO 

   Go to step 3.

3. Shorted wire check (BRAKE LAMP line) 1

   - 1. Turn the vehicle to the ON mode.

   - 2. Check the brake lights without pressing the brake pedal.

   Are the brake lights on?

   YES 

   Go to step 4.

   NO 

   Go to step 5.

4. Shorted wire check (BRAKE LAMP line) 2

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

   - 2. Disconnect the following connector.

   VSA modulator-control unit 38P connector

   - 3. Turn the vehicle to the ON mode.

   - 4. Check the brake lights without pressing the brake pedal.

   Are the brake lights on?

   YES 

   Repair a short to ground in the wire between the brake light relay 5P socket No. 5 and the VSA modulator-control unit 38P connector No. 14.

   NO 

   The BRAKE LAMP wire is OK. Go to step 7.

5. Open wire check (STOP SW line)

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

   - 2. Short the SCS line with the HDS.

   - 3. Disconnect the following connectors.

   PCM connector A (51P)

   Brake pedal position switch 4P connector

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

   Test condition	Vehicle OFF (LOCK) mode
   	PCM connector A (51P): disconnected
   	Brake pedal position switch 4P connector: disconnected
   Test point 1	PCM connector A (51P) No. 25 - Refer to: PCM Connector for Inputs and Outputs (2014 2015) or PCM Connector for Inputs and Outputs (2016) or PCM Connector for Inputs and Outputs (2017 2018 2019 2020)
   Test point 2	Brake pedal position switch 4P connector No. 1

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

   Is there continuity?

   YES 

   The STOP SW wire is OK. Go to step 6.

   NO 

   Repair an open in the wire between the PCM and the brake pedal position switch.

6. PCM check (update or substitution)

   - 1. Reconnect the following connectors.

   PCM connector A (51P)

   Brake pedal position switch 4P connector

   - 2. Update the PCM if it does not have the latest software,

   or substitute a known-good PCM.  Refer to:

   PCM Removal and Installation (2016 2017 2018 2019 2020)

   - 3. Clear the DTC with the HDS.

   - 4. Turn the vehicle to the OFF (LOCK) mode, then to the ON mode.

   - 5. Wait 2 seconds or more without pressing the brake pedal.

   - 6. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame
   59-1 Brake Diag Circuit ON Failure

   Is DTC 59-1 indicated?

   YES 

   Go to step 7.

   NO 

   If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM - Refer to:

   PCM Removal and Installation (2016 2017 2018 2019 2020)

7. VSA modulator-control unit check (update)

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

   - 2. Reconnect the following connector.

   VSA modulator-control unit 38P connector (if disconnected)

   - 3. Update the VSA modulator-control unit if it does not have the latest software.

   - 4. Turn the vehicle to the OFF (LOCK) mode, then to the ON mode.

   - 5. Wait 2 seconds or more without pressing the brake pedal.

   - 6. Check for DTCs with the HDS.

   DTC Description	DTC	Freeze Frame

   Is DTC 59-1 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.