P0719

Diagnostic Chart:

Diagnostic Chart (cont'd):

Wiring Diagram:

CIRCUIT DESCRIPTION

The TCC/Shift Interrupt switch indicates the status of the brake pedal. This normally-closed switch within the Brake Switch Assembly, supplies a B+ signal on the circuit 583 to the PCM. Applying the brake pedal opens the signal voltage circuit. The PCM de-energizes the TCC Solenoid Valve when the PCM receives the signal.

When the PCM detects an open brake switch during accelerations, then DTC P0719 sets. DTC P0719 is a type D DTC.


CONDITIONS FOR SETTING THE DTC

- No Vehicle Speed Sensor (VSS) DTC P0502

- The PCM detects an open TCC/Shift Interrupt switch/circuit (0 volts) for 15 minutes without going off for 2 seconds, and the following sequence of events occurs seven consecutive times:

- The vehicle speed is less than 8 km/h (5 mph);

- Then the vehicle speed is between 8 and 32 km/h (5 and 20 mph) for 4 seconds;

- Then the vehicle speed is greater than 32 km/h (20 mph) for 6 seconds.

ACTION TAKEN WHEN THE DTC SETS

- If pass conditions are not met, the Throttle Position (TP) is greater than 10%, an the VSS is greater than 40 mph, then the brake switch is disregarded for TCC scheduling. This action occurs before the DTC sets.

- The PCM does not illuminate the Malfunction Indicator Lamp (MIL).


CONDITIONS FOR CLEARING THE MIL/DTC

- The PCM turns OFF the MIL after three consecutive ignition cycles without a failure reported.

- 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.

- 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 any poor electrical connections at the PCM. Inspect the wiring at the brake switch assembly. Look for the following conditions:

- 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 an open condition, massage the wiring harness while watching the test equipment for changes.

- Ask the customer about the customer's driving habits. Ask if the customer has any unusual driving conditions (e.g. stop-and-go, expressway, etc.).

- Check for the most current calibration ID. Check for the latest bulletins.

- Inspect the brake switch assembly for proper mounting and adjustment.


TEST DESCRIPTION

The numbers below refer to the step numbers on the diagnostic chart.

3. Step 3 tests for voltage at the brake switch.

6. Step 6 verifies that the TCC/Shift Interrupt switch is functioning normally.

9. Step 9 verifies that circuit 583 is functioning normally at the PCM.