P1811

DTC P1811

Schematic:

Circuit Description
The PCM modifies the transmission line pressure through the Pressure Control (PC) solenoid valve, in order to control shift execution time and shift consistency. The PCM monitors various inputs, and modifies the shift execution and timing by applying a calculated duty cycle to the PC solenoid valve. The PCM alters the shifting based on driving habits, transmission load, and internal transmission condition.
When the PCM detects long shifts that cannot be shortened by shift adapts during the same ignition cycle, then DTC P1811 sets. DTC P1811 is a type C DTC.

Conditions for Running the DTC
- The shift is adaptable.
- The shift adapt is at its limit.

Conditions for Setting the DTC
The shift time is greater than 0.65 second twice during the same trip.

Action Taken When the DTC Sets
- The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
- The PCM commands maximum line pressure.
- The PCM freezes transmission adapt functions.
- 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 P1811 in PCM history.

Conditions for Clearing the DTC
- A scan tool can clear the DTC.
- 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 ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids
Ask the customer about overloading the vehicle, exceeding the trailer-towing limit, or towing in Overdrive.

Test Description

Steps 1-5:

Steps 6-9:

Steps 10-11:

Steps 12-13:

The numbers below refer to the step numbers on the diagnostic table.
2. This step tests for low fluid level, which can cause long shifts.
4. This step tests for low line pressure, which can cause long shifts.