4L80-E / 4L85-E Automatic Transmission

DTC P0719





Test 1-7





Test 8-14

Circuit Description with 4L80-E / 4L85-E Automatic Transmission
The normally open TCC Brake 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 Brake switch, stuck OFF, during decelerations, then DTC P0719 sets. DTC P0719 is a type C DTC.

Conditions for Running the DTC
^ No VSS 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 Brake switch/circuit, 0 volts.

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

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 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
^ Ask about the customer 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 Brake Switch circuit will cause the fuse to open.
^ Inspect the TCC Brake switch for proper mounting and operation.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step isolates the TCC Brake switch as a source for setting the DTC.
5. This step tests for a short to ground between the fuse and the TCC Brake 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.