The brake switch indicates brake pedal status to the PCM. The normally-closed brake switch supplies battery voltage on circuit 420 to the PCM. Applying the brake pedal opens the switch, interrupting voltage to the PCM. Releasing the brake pedal resumes voltage to the PCM. When the PCM senses 0 volts at the brake switch input, the PCM de-energizes the torque converter clutch (TCC) solenoid valve. The PCM disregards the brake switch input for TCC scheduling if there is a brake switch circuit fault (Refer to Diagnostic Aids).
When the PCM detects an open brake switch (stuck ON) during accelerations, then DTC P0719 sets. DTC P0719 is a type D DTC.
• | The ignition switch is in the RUN position. |
• | The system voltage is 8-18 volts. |
DTC P0719 sets if the PCM detects an open brake switch or circuit (0 volts) for 15 minutes and the following conditions occur eight times:
• | The vehicle speed is less than 8 km/h (5 mph); |
• | then, the vehicle speed is 8-32 km/h (5-20 mph) for 3 seconds; |
• | then, the vehicle speed is greater than 32 km/h (20 mph) for 6 seconds. |
• | The PCM does not illuminate the malfunction indicator lamp (MIL). |
• | The PCM stores DTC P0719 in PCM history. |
• | A scan tool clears the DTC from PCM history. |
• | The PCM clears the DTC from PCM history if the vehicle completes 40 consecutive 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 the ignition switch is OFF long enough in order to power down the PCM. |
• | If the PCM detects a brake switch circuit fault, then the brake switch input is disregarded for TCC scheduling. The PCM then uses throttle position and vehicle speed input to determine TCC application and release. Use of these inputs may result in a noticeable harsh apply or abrupt release of the TCC. |
• | Ask about the customer's driving habits. Ask about unusual traffic conditions, and stop-and-go driving. |
• | Inspect the brake switch for proper adjustment. |
• | Inspect the wiring at the PCM, the brake switch connector, and all other circuit connecting points for the following conditions: |
- | A backed out terminal |
- | A damaged terminal |
- | Reduced 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. |
The numbers below refer to the step numbers on the diagnostic table.
Disconnecting the brake switch connector, jumping the circuit, and observing a status change, isolates the brake switch as the source of the DTC.
If circuit 341 shorts to ground, the CRUISE fuse opens.
If the brake switch is properly adjusted, then the brake switch must be replaced.
Replace the PCM only after you have completed the preceding diagnostic steps.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||||||||
Important: Before clearing the DTCs, use the scan tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the PCM. Did the brake switch status change from OPEN to CLOSED? | -- | |||||||||
Refer to General Electrical Diagnosis in Wiring Systems. Is the fuse open? | -- | |||||||||
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics in Wiring Systems, for complete circuit distribution. Inspect circuit 341 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | ||||||||
Refer to Stoplamp Switch Adjustment. Did the brake switch require adjustment? | -- | |||||||||
6 | Replace the brake switch. Refer to Stoplamp Switch Replacement. Is the replacement complete? | -- | -- | |||||||
7 | Inspect circuit 420 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
8 | Repair the wiring as necessary. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
9 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the replacement complete? | -- | -- | |||||||
10 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | System OK |
The brake switch indicates brake pedal status to the PCM. The normally-closed brake switch supplies battery voltage on circuit 420 to the PCM. Applying the brake pedal opens the switch, interrupting voltage to the PCM. Releasing the brake pedal resumes voltage to the PCM. When the PCM senses 0 volts at the brake switch input, the PCM de-energizes the torque converter clutch (TCC) solenoid valve. The PCM disregards the brake switch input for TCC scheduling if there is a brake switch circuit fault (Refer to Diagnostic Aids).
When the PCM detects an open brake switch (stuck ON) during accelerations, then DTC P0719 sets. DTC P0719 is a type D DTC.
• | The ignition switch is in the RUN position. |
• | The system voltage is 8-18 volts. |
DTC P0719 sets if the PCM detects an open brake switch or circuit (0 volts) for 15 minutes and the following conditions occur eight times:
• | The vehicle speed is less than 8 km/h (5 mph); |
• | then, the vehicle speed is 8-32 km/h (5-20 mph) for 3 seconds; |
• | then, the vehicle speed is greater than 32 km/h (20 mph) for 6 seconds. |
• | The PCM does not illuminate the malfunction indicator lamp (MIL). |
• | The PCM stores DTC P0719 in PCM history. |
• | A scan tool clears the DTC from PCM history. |
• | The PCM clears the DTC from PCM history if the vehicle completes 40 consecutive 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 the ignition switch is OFF long enough in order to power down the PCM. |
• | If the PCM detects a brake switch circuit fault, then the brake switch input is disregarded for TCC scheduling. The PCM then uses throttle position and vehicle speed input to determine TCC application and release. Use of these inputs may result in a noticeable harsh apply or abrupt release of the TCC. |
• | Ask about the customer's driving habits. Ask about unusual traffic conditions and stop-and-go driving. |
• | Inspect the brake switch for proper adjustment. |
• | Inspect the wiring at the PCM, the brake switch connector, and all other circuit connecting points for the following conditions: |
- | A backed out terminal |
- | A damaged terminal |
- | Reduced 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. |
The numbers below refer to the step numbers on the diagnostic table.
Disconnecting the brake switch connector, jumping the circuit, and observing a status change, isolates the brake switch as the source of the DTC.
If circuit 341 shorts to ground, the CRUISE fuse opens.
If the brake switch is properly adjusted, then the brake switch must be replaced.
Replace the PCM only after you have completed the preceding diagnostic steps.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Was the Powertrain On-Board Diagnostic (OBD) System Check performed? | -- | ||||||||
Important: Before clearing the DTCs, use the scan tool in order to record the Failure Records. Using the Clear Info function erases the Failure Records from the PCM. Did the brake switch status change from OPEN to CLOSED? | -- | |||||||||
Refer to General Electrical Diagnosis in Wiring Systems. Is the fuse open? | -- | |||||||||
Important: The condition that affects this circuit may exist in other connecting branches of the circuit. Refer to Power Distribution Schematics in Wiring Systems, for complete circuit distribution. Inspect circuit 341 for a short to ground. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | -- | ||||||||
Refer to Stoplamp Switch Adjustment. Did the brake switch require adjustment? | -- | |||||||||
6 | Replace the brake switch. Refer to Stoplamp Switch Replacement. Is the replacement complete? | -- | -- | |||||||
7 | Inspect circuit 420 for an open. Refer to General Electrical Diagnosis in Wiring Systems. Was the condition found? | -- | ||||||||
8 | Repair the wiring as necessary. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | -- | |||||||
9 | Replace the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the replacement complete? | -- | -- | |||||||
10 | Perform the following procedure in order to verify the repair:
Has the test run and passed? | -- | System OK |