P0719

Circuit Description
The normally open TCC/Stoplamp switch indicates brake pedal status to the Powertrain Control Module (PCM). Applying the brake pedal closes the switch, supplying voltage to the PCM. Releasing the brake pedal interrupts voltage to the PCM.

If the PCM detects an open TCC/Stoplamp switch (stuck OFF) during decelerations, then DTC P0719 sets. DTC P0719 is a type D DTC.

Conditions for Running the DTC
^ No OSS sensor DTC P0722 or P0723.
^ The following sequence of events occur:
1. the vehicle speed is greater than 32 km/h (20 mph) for 6 seconds.
2. Then the vehicle speed is 8-32 km/h (5-20 mph) for 3 seconds.
3. Then the vehicle speed is less than 8 km/h (5 mph).
4. DTC P0719 has not passed.

Conditions for Setting the DTC
^ All conditions are met for ten occurrences.
^ The PCM detects a closed TCC/Stoplamp switch/circuit (0 volts).

Action Taken When the DTC Sets
^ The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM stores DTC P0719 in PCM history.

Conditions for Clearing the DTC
^ 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.

Diagnostic Aids
^ Inspect the wiring at the PCM, the TCC/Stoplamp 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, massage the wiring harness while watching the test equipment for a change.
^ Ask about the customer's driving habits and any unusual driving conditions he or she might have, such as stop and go traffic or expressway driving.
^ A short in the stoplamp circuit will cause the fuse to open.
^ Inspect the TCC/Stoplamp switch for proper mounting and adjustment.
^ First diagnose and clear any engine DTCs codes that are present. Then inspect for any transmission DTCs that may have reset.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step isolates the TCC/Stoplamp switch as a source for setting the DTC.
5. This step tests for a short to ground between the fuse and the TCC/Stoplamp switch.
7. This step tests for a short to ground in circuit 17.
8. This step removes the PCM from circuit 17 as the source of a short to ground.