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 brake pedal is applied.
If the PCM detects an open TCC/Stop lamp switch circuit during accelerations, then DTC P0719 sets. DTC P0719 is a type C DTC.
• | 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 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 brake 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 brake fuse circuit (CKT 441).
This step tests for a short to ground in the TCC brake switch signal circuit (CKT 420), 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 Powertrain Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Engine Controls in Engine Controls - 6.0L or Diagnostic System Check - Engine Controls in Engine Controls - 8.1L | ||||||
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: When you are performing service on or near the SIR components or the SIR wiring, you must disable the SIR system. Refer to Disabling the SIR System. Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary SIR system repairs. 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 General Electrical Diagnosis 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 brake fuse circuit (CKT 441) 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 (CKT 420) 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 Hydraulic Brakes. 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 brake fuse circuit (CKT 441) for a short to ground. 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 signal circuit (CKT 420) for a short to ground. Did you find and correct the condition? | -- | Go to Step 16 | -- | ||||||
15 | Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 6.0L or Powertrain Control Module Replacement in Engine Controls - 8.1L. 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? | -- | System OK | Go to Step 1 |