P1811

DTC P1811

Steps 1-5:

Step 6:

Step 12:

Steps 13 & 14:

Circuit Description

Important: Refer to the 2003 Transmission Unit Repair Manual (TURM) for Fluid Flow illustration.

An adaptive modifier modifies the transmission pressure. The adaptive modifier controls the shift execution time. This DTC monitors the time required to accomplish the shift. If the shift takes longer than 0.65 second, and the adaptive modifier cannot shorten this time, then a counter iterates.
DTC P1811 sets when this counter reaches its limit. DTC P1811 is a type C DTC.

Conditions for Running the DTC
An adaptable shift has occurred.

Conditions for Setting the DTC
One of the following conditions occurs twice during the same trip:

Condition 1
^ The 1-2 shift is longer than 0.65 second.
^ The 1-2 shift adapt has reached its limit.

Condition 2
^ The 2-3 shift is longer than 0.65 second.
^ The 2-3 shift adapt has reached its limit.

Condition 3
^ The 3-4 shift is longer than 0.65 second.
^ The 3-4 shift adapt has reached its limit.

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 adaptive 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 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 DTC passes.

Diagnostic Aids
^ Ask the customer about overloading the vehicle, exceeding the trailer-towing limit, or towing in Overdrive.
^ Ensure that the PCM has the latest calibration update.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step reviews the 1-2 adapt cells. If the pressure readings match or exceed the value listed in the value column, then the PCM modifies the base line pressure on a 1-2 shift. This modification adjusts the holding effort of a clutch or band.
4. This step reviews the 2-3 adapt cells. If pressure readings match or exceed the value listed in the value column, then the PCM modifies the base line pressure on a 2-3 shift. This modification adjusts the holding effort of a clutch or band.
5. This step reviews the 3-4 adapt cells. If pressure readings match or exceed the value listed in the value column, then the PCM modifies the base line pressure on a 3-4 shift. This modification adjusts the holding effort of a clutch or band.
6. This step inspects or repairs any of the components listed. A faulty component may lead to a maximum adapt and long shift during a 1-2 upshift.
7. This step inspects or repairs any of the components listed. A faulty component may lead to a maximum adapt and long shift during a 2-3 upshift.
8. This step inspects or repairs any of the components listed. A faulty component may lead to a maximum adapt and long shift during a 3-4 upshift.
9. This step inspects components located within the valve body, if the fluid pressure gage readings do not match the commanded PC solenoid valve current to line pressure located in the value column.