DTC P0A11

DTC P0A11 : DC-DC Converter Activation Circuit Malfunction

NOTE: Before you troubleshoot, review the general troubleshooting information - Refer to: How to Troubleshoot the Fuel and Emissions Systems, or How to Troubleshoot the A/T System (2014 2015), or How to Troubleshoot the Brake Booster Pressure Monitoring System (2016 2017 2018 2019 2020), or How to Troubleshoot the Fuel and Emissions Systems(With Auto Idle Stop System) (2016) .

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P0A11 DC-DC Converter Activation Circuit Malfunction

DTC (PGM-FI)

Problem verification

-1. Turn the vehicle to the ON mode.

- 2. Clear the DTC with the HDS.

- 3. Test-drive the vehicle under the auto idle stop system operating condition, and stop the engine using auto idle stop.

- 4. Check for Pending or Confirmed DTCs with the HDS.

DTC Description	Confirmed DTC	Pending DTC	Freeze Frame
P0A11 DC-DC Converter Activation Circuit Malfunction

Is DTC P0A11 indicated?

YES

The failure is duplicated. Go to step 2.

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the DC-DC converter and the PCM. 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.

Determine possible failure area (CST line open, others)

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

- 2. Jump the SCS line with the HDS.

- 3. Disconnect the following connector.

PCM connector A (51P)

- 4. Turn the vehicle to the ON mode.

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

Test condition	Vehicle ON mode
	PCM connector A (51P): disconnected
Test point 1	PCM connector A (51P) No. 2 - Refer to: PCM Connector for Inputs and Outputs (2017 2018 2019 2020), or PCM Connector for Inputs and Outputs (2014 2015), or PCM Connector for Inputs and Outputs (2016)
Test point 2	Body ground

Is there battery voltage?

YES

Go to step 4.

Go to step 3.

Open wire check (CST line)

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

- 2. Disconnect the following connector.

DC-DC converter connector A (3P)

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

Test condition	Vehicle OFF (LOCK) mode
	PCM connector A (51P): disconnected
	DC-DC converter connector A (3P): disconnected
Test point 1	DC-DC converter connector A (3P) No. 2
Test point 2	PCM connector A (51P) No. 2 - Refer to: PCM Connector for Inputs and Outputs (2017 2018 2019 2020), or PCM Connector for Inputs and Outputs (2014 2015), or PCM Connector for Inputs and Outputs (2016)

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

Is there continuity?

YES

Replace the DC-DC converter .

Repair an open in the CST wire between the PCM (A2) and the DC-DC converter.

Shorted wire check (CST line to power)

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

- 2. Disconnect the following connector.

DC-DC converter connector A (3P)

- 3. Turn the vehicle to the ON mode.

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

Test condition	Vehicle ON mode
	PCM connector A (51P): disconnected
	DC-DC converter connector A (3P): disconnected
Test point 1	DC-DC converter connector A (3P) No. 2
Test point 2	Body ground

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

Is there any voltage?

YES

Repair a short to power in the CST wire between the PCM (A2) and the DC-DC converter.

The CST wire is OK. Substitute a known-good PCM - Refer to: PCM Removal and Installation (2014 2015), or PCM Removal and Installation (2016) , then recheck:?

If DTC P0A11 is not indicated, replace the original PCM - Refer to: PCM Removal and Installation (2014 2015), or PCM Removal and Installation (2016) .
If DTC P0A11 is indicated again, replace the DC-DC converter .