The TCC/Stop lamp switch indicates the brake pedal status. The normally-closed TCC/Stop lamp switch supplies a B+ signal to the powertrain control module (PCM). The signal voltage circuit opens when the brakes are applied.
If the PCM detects an open TCC/Stop lamp switch circuit during accelerations, DTC P0719 sets. DTC P0719 is a type C DTC.
This diagnostic procedure supports the following DTC:
DTC P0719 Brake Switch Circuit Low Voltage
• | No AT VSS DTC P0502 or DTC P0503. |
• | The following sequence of events occurs: |
1. | The vehicle speed is less than 8 km/h (5 mph). |
2. | Then the vehicle speed is 8-40 km/h (5-25 mph) for 1.7 seconds. |
3. | Then the vehicle speed is greater than 40 km/h (25 mph) for 7 seconds. |
• | All conditions are met for 8 occurrences. |
• | The PCM detects an open TCC/Stop lamp switch/circuit, 0 volts, for 15 minutes. |
• | The PCM does not illuminate the malfunction indicator lamp (MIL). |
• | For TCC scheduling, the PCM disregards the brake switch state if the throttle angle sensor is greater than 1.5 percent and the vehicle speed is greater than 32 km/h (20 mph). |
• | The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records. |
• | 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 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 DTC passes. |
Inspect the stop lamp switch for proper mounting and operation.
The numbers below refer to the step numbers on the diagnostic table.
This step tests for TCC/Stop lamp switch voltage to the PCM connector.
This step isolates the TCC/Stop lamp switch as a source for setting the DTC.
This step tests for a short to ground in the ignition 3 voltage circuit, ignition voltage, to the TCC/Stop lamp switch.
This step tests for a short to ground in the TCC brake switch, from the TCC/Stop lamp switch to the PCM.
This step isolates the PCM as a source for causing the fuse to open.
Step | Action | Value(s) | Yes | No | ||||||
---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||
2 |
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. Caution: Refer to SIR Caution in the Preface section. Does the scan tool TCC Brake Switch indicate CLOSED, when the brake pedal is not applied? | -- | Go to Intermittent Conditions in Engine Controls - 6.0L or Intermittent Conditions in Engine Controls - 8.1L | Go to Step 3 | ||||||
3 |
Refer to Circuit Protection - Fuses in Wiring Systems. Is the fuse open? | -- | Go to Step 10 | Go to Step 4 | ||||||
Does the test lamp illuminate? | -- | Go to Step 15 | Go to Step 5 | |||||||
5 |
Does the voltage measure within the specified value? | 10-13 V | Go to Step 7 | Go to Step 6 | ||||||
6 |
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. Test the ignition 3 voltage circuit for an open. Did you find and correct the condition? | -- | Go to Step 16 | -- | ||||||
Does the test lamp illuminate? | -- | Go to Step 9 | Go to Step 8 | |||||||
8 |
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. Test the TCC brake switch signal circuit for an open. Did you find and correct the condition? | -- | Go to Step 16 | -- | ||||||
9 | Replace the TCC/Stop lamp switch. Refer to Stop Lamp Switch Replacement in Lighting Systems. Did you complete the replacement? | -- | Go to Step 16 | -- | ||||||
Does the fuse open with the brake pedal applied? | -- | Go to Step 11 | Go to Step 12 | |||||||
11 |
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. Test the ignition 3 voltage circuit for a short to ground. Refer to Testing for a Short to Voltage in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | -- | ||||||
With the key in the RUN position, release the brake pedal. Does the fuse open when the brake pedal is released? | -- | Go to Step 13 | Go to Intermittent Conditions in Engine Controls - 6.0L or Intermittent Conditions in Engine Controls - 8.1L | |||||||
Does the fuse open? | -- | Go to Step 14 | Go to Step 15 | |||||||
14 |
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. Test the TCC brake switch for a short to ground. Refer to Testing for Short to Ground in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | -- | ||||||
15 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 16 | -- | ||||||
16 | Perform the following procedure in order to verify the repair:
Does the TCC Brake Switch indicate CLOSED when the brake pedal is not applied, then indicate OPEN when the brake pedal is applied? | -- | Go to Step 17 | Go to Step 2 | ||||||
17 | With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK |