GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2007 🢒 Vibe - FWD 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0724

Circuit Description

The brake switch indicates brake pedal status to the powertrain control module (PCM). When the brake pedal is operated, the switch sends a signal to the PCM, the PCM then cancels the operation of the torque converter clutch (TCC) lock-up while braking is in progress. This prevents the engine from stalling.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0724 Brake Switch Circuit High Voltage

Conditions for Running the DTC
    • The switch does not turn off even once the vehicle is driven (2-trip detection logic).
    • The ignition is ON.

Conditions for Setting the DTC

The PCM detects a closed brake switch circuit, 12 volts, without changing for 2 seconds and the following events occur 8 times:

The vehicle must stop and go from 3 km/h (2 mph) to 30 km/h (19 mph) 10 times for 2 driving cycles before detecting a malfunction.

Action Taken When the DTC Sets
    • The PCM illuminates the malfunction indicator lamp (MIL).
    • The PCM stores DTC P0724 in PCM history.

Conditions for Clearing the DTC
    • A scan tool can clear the DTC.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.
    • The PCM cancels the DTC default actions when the fault no longer exists and/or the ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids

Inspect the brake switch for proper mounting and operation.

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step isolates the brake switch as a source for Setting the DTC.

DTC P0724

Step

Action

Values

Yes

No

Schematic Reference: Automatic Transmission Controls Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.

    3. Important: Before clearing the DTC, use the scan tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the powertrain control module (PCM).

  3. Record the DTC Failure Records.
  4. Clear the DTC.
  5. Select Brake Switch on the scan tool.

    6. Caution: Refer to SIR Caution in the Preface section.

  6. Disconnect the brake switch connector from the brake switch.

Did the Brake Switch status change from Closed to Open?

--

Go to Step 3

Go to Step 4

3

Replace the brake switch. Refer to Stop Lamp Switch Replacement.

Did you complete the replacement?

--

Go to Step 6

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4

Test the signal circuit of the brake switch for a short to power.

Did you find and correct the condition?

--

Go to Step 6

Go to Step 5

5

Replace the PCM. Refer to Powertrain Control Module Programming and Setup.

Did you complete the replacement?

--

Go to Step 6

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6

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear Info.
  3. Turn ON the ignition, with the engine OFF.
  4. Apply and release the brake pedal.
  5. Verify that the scan tool TCC Brake Switch status indicates Open, 0 volts, for 2 seconds.
  6. Select Specific DTC.
  7. Enter DTC P0724.

Has the test run and passed?

0 V

System OK

Go to Step 1