DTC C1270-15

WARNING: This page is about a different car, the 2022 Honda Accord, 2021 Honda Accord, 2020 Honda Accord, 2019 Honda Accord, and 2018 Honda Accord. However, it is still accessible from the selected car via links, so may be relevant.

DTC C1270-15 : Automatic Brake Hold Switch Signal Circuit Open

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

DTC Description	DTC
C1270-15 Automatic Brake Hold Switch Signal Circuit Open

DTC (VSA)

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.

DTC Description	DTC
C1270-15 Automatic Brake Hold Switch Signal Circuit Open

Is DTC C1270-15 indicated?

YES

The failure is duplicated. Go to step 2.

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

Open wire check (BRAKE HOLD line) 1

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

-2. Disconnect the following connector.

Automatic brake hold switch 6P connector *1

Automatic brake hold switch 12P connector *2

*1: Automatic brake hold switch 6P connector type

*2: Automatic brake hold switch 12P connector type

-3. Turn the vehicle to the ON mode.

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

Test condition	Vehicle ON mode
	Automatic brake hold switch 6P connector *1: disconnected
	Automatic brake hold switch 12P connector *2: disconnected
Test point 1	Automatic brake hold switch 6P connector (female terminals) No. 3 1: Automatic brake hold switch 12P connector (female terminals) No. 12 2:
Test point 2	Body ground

*1: Automatic brake hold switch 6P connector type

*2: Automatic brake hold switch 12P connector type

Automatic brake hold switch 6P connector type

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

Automatic brake hold switch 12P connector type

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

Is there about 5 V?

YES

The BRAKE HOLD wire is OK. Go to step 3.

If about 12 V is indicated. Go to step 5.

If about 0 V is indicated. Go to step 7.

Open wire check (GND line)

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

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

Test condition	Vehicle OFF (LOCK) mode
	Automatic brake hold switch 6P connector *1: disconnected
	Automatic brake hold switch 12P connector *2: disconnected
Test point 1	Automatic brake hold switch 6P connector (female terminals) No. 1 1: Automatic brake hold switch 12P connector (female terminals) No. 6 2:
Test point 2	Body ground

*1: Automatic brake hold switch 6P connector type

*2: Automatic brake hold switch 12P connector type

Automatic brake hold switch 6P connector type

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

Automatic brake hold switch 12P connector type

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

Is there continuity?

YES

Go to step 4.

Repair an open in the wire between the automatic brake hold switch and body ground (G501).

Automatic brake hold switch check
-1. Check the automatic brake hold switch .

Is the automatic brake hold switch OK?

YES

Check for loose terminals and poor connections in the VSA modulator-control unit 46P connector. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the VSA modulator-control unit .

NO

Replace the automatic brake hold switch .

Shorted wire check (BRAKE HOLD line to power)

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

-2. Disconnect the following connector.

Gauge control module connector A (32P)

-3. Turn the vehicle to the ON mode.

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

Test condition	Vehicle ON mode
	Automatic brake hold switch 6P connector *1: disconnected
	Automatic brake hold switch 12P connector *2: disconnected
	Gauge control module connector A (32P): disconnected
Test point 1	Automatic brake hold switch 6P connector (female terminals) No. 3 1: Automatic brake hold switch 12P connector (female terminals) No. 12 2:
Test point 2	Body ground

*1: Automatic brake hold switch 6P connector type

*2: Automatic brake hold switch 12P connector type

Automatic brake hold switch 6P connector type

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

Automatic brake hold switch 12P connector type

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

Is there 0.1 V or more?

YES

Repair a short to power in the wire between the automatic brake hold switch and the gauge control module.

Go to step 6.

Gauge control module check (substitution)

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

-2. Substitute a known-good gauge control module .

-3. Reconnect the following connectors.

Automatic brake hold switch 6P connector *1

Automatic brake hold switch 12P connector *2

Gauge control module connector A (32P)

*1: Automatic brake hold switch 6P connector type

*2: Automatic brake hold switch 12P connector type

-4. Turn the vehicle to the ON mode.

-5. Clear the DTC with the HDS.

-6. Turn the vehicle to the OFF (LOCK) mode, then to the ON mode.

-7. Check for DTCs with the HDS.

DTC Description	DTC
C1270-15 Automatic Brake Hold Switch Signal Circuit Open

Is DTC C1270-15 indicated?

YES

Check for loose terminals and poor connections in the VSA modulator-control unit 46P connector. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the VSA modulator-control unit .

Replace the original gauge control module .

Open wire check (BRAKE HOLD line) 2

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

-2. Disconnect the following connector.

Gauge control module connector A (32P)

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

Test condition	Vehicle OFF (LOCK) mode
	Automatic brake hold switch 6P connector *1: disconnected
	Automatic brake hold switch 12P connector *2: disconnected
	Gauge control module connector A (32P): disconnected
Test point 1	Automatic brake hold switch 6P connector (female terminals) No. 3 1: Automatic brake hold switch 12P connector (female terminals) No. 12 2:
Test point 2	Gauge control module connector A (32P) No. 32