P0719

Diagnostic Chart:

Wiring Diagram:

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 brake switch (stuck OFF) during decelerations, then DTC P0719 sets. DTC P0719 is a type D DTC.

CONDITIONS FOR SETTING THE DTC
No Output Speed Shaft (OSS) Sensor DTC P0722 or P0723.
The PCM detects an open TCC stoplamp switch/circuit (0 volts) and the following sequence of events occurs ten consecutive times:
1. The vehicle speed is greater than 32 km/h (20 mph) for 6 seconds.
2. Then the vehicle speed is 832 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.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
^ For TCC scheduling, the PCM disregards the brake switch state if the Throttle Position (TP) Sensor is greater than 12% and the vehicle speed is greater than 20 mph.

CONDITIONS FOR CLEARING THE DTC
1. A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.
2. The PCM cancels the DTC default actions when the fault no longer exists and the ignition is OFF long enough in order to power down the PCM.

DIAGNOSTIC AIDS
^ Inspect the wiring for poor electrical connections at the PCM. Inspect the wiring for poor electrical connections at the TCC brake switch. Look for the following problems:
- A bent terminal.
- A backed out terminal.
- A damaged terminal.
- Poor terminal tension.
- A chafed wire.
- A broken wire inside the insulation.
^ 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.
^ Inspect the break 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 brake switch as a source for setting the DTC.
5. This step tests for a short to ground between the fuse and the TCC Stop Light 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.