P0724

DIAGNOSTIC TROUBLE CODE (DTC) P0724 BRAKE SWITCH CIRCUIT HIGH





Circuit Description
The brake switch is used to indicate brake pedal status to the Powertrain Control Module (PCM). The brake switch is a normally-open switch. Applying the brake pedal closes the switch, supplying voltage to the PCM. Releasing the brake pedal interrupts voltage to the PCM. When the PCM sees 12 volts at the brake switch input, the PCM de-energizes the Torque Converter Clutch Solenoid Valve (TCC Sol. Val.).
When the PCM detects a closed brake switch during accelerations, then Diagnostic Trouble Code (DTC) P0724 sets.

Conditions For Setting The DTC
This DTC will set if the PCM detects a closed brake switch/circuit (12 volts) during vehicle acceleration and the following conditions occur six consecutive times:
- Vehicle speed is less than 8 km/h; then vehicle speed is between 8 and 32 km/h for four seconds; then vehicle speed is greater than 32 km/h for six seconds.

Action Taken When The DTC Sets
- PCM does not illuminate the Malfunction Indicator Lamp (MIL).
- DTC P0724 will be stored in PCM memory.

Conditions For Clearing The DTC
- When the PCM has seen a change in the brake switch state and three consecutive ignition cycles.
- History DTCs can be cleared by using a Scan Tool.

Diagnostic Aids
- Ask customer about driving habits and/or unusual traffic conditions, such as heavy stop and go driving.
- Check brake switch for proper adjustment.
- Inspect the wiring for poor electrical connections at the PCM and at the brake switch. Look for possible bent, backed out, deformed or damaged terminals. Check for weak terminal tension as well. Also check for chafed wires that could short to bare metal or other wiring. Inspect for broken wire inside the insulation.
- If diagnosing for a possible intermittent short or open condition, move or massage the wiring harness while observing test equipment for a change.

Test Description
The numbers below refer to the step numbers on the diagnostic chart.
2. Disconnecting the brake switch connector, and observing a status change, isolates the brake switch as the source for setting the DTC.
3. If the brake switch is adjusted properly, then the brake switch must be replaced.
4. This step will inspect circuit 534 for a short to power if the status on the scan tool never changed from "Closed" to "Open." If a short is found, make the appropriate repair.
5. Replacement of the PCM only after the brake switch and all related circuitry have been properly inspected or repaired.





DTC P0724 - Brake Switch Circuit High