For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC P07224: Brake Switch Circuit High Input

### Circuit/System Description

The TCC brake switch indicates brake pedal status to the TCM. The TCC brake switch indicates brake pedal applied or released. The normally-closed switch indicates the battery supplies voltage to transmission control module (TCM). Apply the brake pedal to active the TCC brake switch, disconnect the PCM voltage. When the TCM receives a 0 volts voltage at the TCC brake switch input, the TCM turns OFF the torque converter clutch pulse width modulation solenoid valve.

DTC P0724 can be set if a closed parking brake switch (indicates the pedal is released) is detected by the TCM in a series of accelerations. DTC P0724 is a type C DTC.

### Conditions for Running the DTC

• | Active the ignition voltage.

• | DTCs P0722, P0723, P0724 are not set.

### Conditions for Setting the DTC

When the following conditions occur 8 times continuously, the TCC brake switch indicates a continuous closed (12 volts):

• | The vehicle speed is greater than 32 km/h (20 mph) for 6 seconds.

• | Then the vehicle speed decreases to 8 km/h (5 mph) and takes 4 seconds.

• | At last, the vehicle speed is less than 8 km/h 5 mph).

### Action Taken When the DTC Sets

DTC P0724 is a type C DTC.

### Conditions for Clearing the DIC/DTC

DTC P0724 is a type C DTC.

### Diagnostic Aids

• | Inspect the controller, components and all other circuit attaching points for an intermittent.

• | Inspect the circuit wiring for an intermittent.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### DTC Type Reference

• | Diagnostic Trouble Code (DTC) Type Definitions

• | Diagnostic Trouble Code (DTC) List/Type

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

#### Special Tools

J 35616 GM-Approved Terminal Test Kit

### Circuit/System Testing

1. Install the scan tool; turn the ignition switch to ON position.

Note: Before clearing the DTCs, use the scan tool to record the Failure Records; use the Clear Info. function to erase the Failure Records from the TCM.

2. Record the DTC Failure Records
3. Clearing Diagnostic Trouble Codes
4. Select TCC Brake Switch on the scan tool
5. Disconnect the brake switch connector from the brake switch. Observe if the Status of the TCC Brake Switch displayed on the scan tool change from CLOSED to OPEN.

⇒ | If it changes to OPEN, replace the brake switch.

⇒ | If there is no change, test the brake switch signal circuit for a short to voltage. If the circuit/connection test is normal, replace the TCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Input and Output Speed Sensor Replacement