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For 1990-2009 cars only

DTC P0724 Brake Switch Circuit High Input 2.4L Vin T


Object Number: 244790  Size: MF
Automatic Transmission Components 2.4L
Automatic Transmission Controls Schematics 2.4L
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The brake switch reports brake pedal status to the Powertrain Control Module (PCM). This normally-closed switch supplies battery voltage on circuit 420 to the PCM. Applying the brake pedal opens the switch, interrupting voltage to the PCM. If the PCM receives a zero voltage signal at the brake switch input, and the Torque Converter Clutch (TCC) is engaged, the PCM de-energizes the Torque Converter Clutch Solenoid Valve (TCC Sol. Valve).

When the PCM detects a continuously closed brake switch (pedal released) during a period, including a number of decelerations, then DTC P0724 sets. DTC P0724 is a type D DTC.

Conditions for Setting the DTC

    • No VSS DTCs P0502 or P0503.
    • The vehicle speed is greater than 32 km/h (20 mph) for more than 6 seconds.
    • The vehicle speed decreases to 8 km/h (5 mph) and takes more than 4 seconds.
    • The vehicle speed is less than 8 km/h (5 mph).
    • The above conditions must occur more than 7 times with the brake switch signal indicating continuously Closed, without being open for more than 2 seconds.

Action Taken When the DTC Sets

The PCM does not illuminate the Malfunction Indicator Lamp (MIL).

Conditions for Clearing the DTC

A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.

Diagnostic Aids

    • Ensure that the brake switch is properly adjusted.
    • Inspect the wiring at the PCM, the brake switch connector and all other circuit connecting points for the following conditions:
       - A bent terminal
       - A backed out terminal
       - A damaged terminal
       - Poor terminal tension
       - A chafed wire
       - A broken wire inside the insulation
       - Moisture intrusion
       - Corrosion
    • When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change.

Test Description

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

  1. A scan tool display that changes from Closed to Open, when the brake switch is disconnected, indicates a faulty brake switch.

DTC P0724 TCC Brake Switch Circuit High Input (2.4L)

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Install the Scan Tool .
  2. With the engine OFF, turn the ignition switch to the RUN position.
  3. Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. Using the Clear Info function will erase the stored Freeze Frame and Failure Records from the PCM.

  4. Record the DTC Failure Records.
  5. Select Brake Switch on the scan tool.
  6. Disconnect the brake switch connector.

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 in Hydraulic Brakes.

Is the replacement complete?

--

Go to Step 7

--

4

Inspect circuit 420 for a short to power. Repair circuit 420 if necessary. Refer to General Electrical Diagnosis in Wiring Systems.

Was a condition found and corrected?

--

Go to Step 7

Go to Step 5

5

Inspect circuits 420 and 39 for a short together. Repair circuits 420 or 39 if necessary. Refer to General Electrical Diagnosis in Wiring Systems.

Was a condition found and corrected?

--

Go to Step 7

Go to Step 6

6

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls.

Is the replacement complete?

--

Go to Step 7

--

7

Perform the following procedure to verify your repair:

  1. Use the scan tool to clear DTC information.
  2. Operate the vehicle under the following conditions:
  3. • Turn the ignition switch to the RUN position.
    • Apply the brake pedal.
    • The Brake Switch must be Open (pedal applied) for more than 2 seconds.
  4. Select Specific DTC.
  5. Enter DTC P0724.

Has the test run and passed?

--

System OK

Go to Step 1

DTC P0724 Brake Switch Circuit High Input 3.1L Vin M


Object Number: 193602  Size: MF
Automatic Transmission Components 3.1L
Automatic Transmission Controls Schematics 3.1L
OBD II Symbol Description Notice
Handling ESD Sensitive Parts Notice

Circuit Description

The brake switch reports brake pedal status to the Powertrain Control Module (PCM). This normally-closed switch supplies battery voltage on circuit 420 to the PCM. Applying the brake pedal opens the switch, interrupting voltage to the PCM. If the PCM receives a zero voltage signal at the brake switch input, and the Torque Converter Clutch (TCC) is engaged, the PCM de-energizes the Torque Converter Clutch Solenoid Valve (TCC Sol. Valve).

When the PCM detects a continuously closed brake switch (pedal released) during a period, including a number of decelerations, then DTC P0724 sets. DTC P0724 is a type D DTC.

Conditions for Setting the DTC

    • No VSS DTCs P0502 or P0503.
    • The vehicle speed is greater than 32 km/h (20 mph) for more than 6 seconds.
    • The vehicle speed decreases to 8 km/h (5 mph) and takes more than 4 seconds.
    • The vehicle speed is less than 8 km/h (5 mph).
    • The above conditions must occur more than 7 times with the brake switch signal indicating continuously Closed, without being Open for more than 2 seconds.

Action Taken When the DTC Sets

The PCM does not illuminate the Malfunction Indicator Lamp (MIL).

Conditions for Clearing the DTC

A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.

Diagnostic Aids

    • Ensure that the brake switch is properly adjusted.
    • Inspect the wiring at the PCM, the brake switch connector and all other circuit connecting points for the following conditions:
       - A bent terminal
       - A backed out terminal
       - A damaged terminal
       - Poor terminal tension
       - A chafed wire
       - A broken wire inside the insulation
       - Moisture intrusion
       - Corrosion
    • When diagnosing for an intermittent short or open condition, massage the wiring harness while watching the test equipment for a change.

Test Description

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

  1. A scan tool display that changes from Closed to Open, when the brake switch is disconnected, indicates a faulty brake switch.

DTC P0724 TCC Brake Switch Circuit High Input (3.1L)

Step

Action

Value(s)

Yes

No

1

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

  1. Install the Scan Tool .
  2. With the engine OFF, turn the ignition switch to the RUN position.
  3. Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. Using the Clear Info function will erase the stored Freeze Frame and Failure Records from the PCM.

  4. Record the DTC Failure Records, then clear the DTC.
  5. Select Brake Switch on the scan tool.
  6. Disconnect the brake switch connector.

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 in Hydraulic Brakes.

Is the replacement complete?

--

Go to Step 7

--

4

Inspect circuit 420 for a short to power. Repair circuit 420 if necessary. Refer to General Electrical Diagnosis in Wiring Systems.

Was a condition found and corrected?

--

Go to Step 7

Go to Step 5

5

Inspect circuits 420 and 39 for a short together. Repair circuits 420 or 39 if necessary. Refer to General Electrical Diagnosis in Wiring Systems.

Was a condition found and corrected?

--

Go to Step 7

Go to Step 6

6

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls.

Is the replacement complete?

--

Go to Step 7

--

7

Perform the following procedure to verify your repair:

  1. Use the scan tool to clear DTC information.
  2. Operate the vehicle under the following conditions:
  3. • Turn the ignition switch to the RUN position.
    • Apply the brake pedal.
    • The Brake Switch must be Open (pedal applied), for more than 2 seconds.
  4. Select Specific DTC.
  5. Enter DTC P0724.

Has the test run and passed?

--

System OK

Go to Step 1