P1811

DTC P1811

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provide an overview of each diagnostic category.



DTC Descriptors
DTC P1811
- Maximum Adapt and Long Shift




Circuit/System Description

The transmission pressure is modified by an adaptive modifier, which controls the shift execution time. This diagnostic tests 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 increases by 1.


Conditions for Running the DTC

* The shift is adaptable.
* The 1-2, 2-3, or 3-4 shift adapt cell has reached the limit.



Conditions for Setting the DTC

The 1-2, 2-3, or 3-4 shift is longer than 0.65 second, twice in 1 trip.


Action Taken When the DTC Sets

* DTC P1811 is a type C DTC.
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.



Conditions for Clearing the DTC

DTC P1811 is a type C DTC.


Reference Information
Schematic Reference

Automatic Transmission Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views
Electrical Information Reference

* Circuit Testing
* Connector Repairs
* Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs

DTC Type Reference

* Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
* Diagnostic Trouble Code (DTC) List/Type (Diagnostic Trouble Code Descriptions)

Scan Tool Reference

Control Module References for scan tool information


Circuit/System Verification

Ensure the transmission fluid level is at the proper level by performing the Transmission Fluid Check (Testing and Inspection) . Ensure the line pressure is within specification by performing the Line Pressure Check (Line Pressure Check Procedure) .


Circuit/System Testing

1. Perform the Transmission Fluid Check (Testing and Inspection) .

• If the level is not within specifications, repair as necessary.

2. Perform the Line Pressure Check (Line Pressure Check Procedure) .

• If the pressures are not within specifications, inspect and repair the following components:


* Oil filter and seal missing, plugged, or damaged
Refer to Automatic Transmission Fluid Filter and Seal Replacement (Service and Repair) .
* Spacer plate and gasket damaged or not assembled correctly
Refer to Control Valve Body and Spacer Plate Assemble (Overhaul) .
* PC solenoid valve damaged or contaminated
* Pressure regulator valve line-up binding or damaged
* Torque signal valve line-up binding or damaged
Refer to Control Valve Body Disassemble (Without Touch Activated Power) (Overhaul)Control Valve Body Disassemble (With Touch Activated Power) (Overhaul) .
* Oil pump assembly damaged or missing components
Refer to Transmission Fluid Pump Disassemble (Overhaul) .

3. Using the scan tool, observe the shift times for the 1-2 upshift. The 1-2 shift time should be less than 0.65 second.

• If the shift time is greater than 0.65 second, inspect and repair the following components:


* 1-2 accumulator piston seals rolled or damaged
* 1-2 accumulator piston and pin missing, binding, or damaged
Refer to Accumulator Components Disassemble (Overhaul) .
* Forward servo assembly damaged or not assembled correctly
Refer to Forward Servo Removal (Overhaul) .
* Oil pump assembly damaged or missing components
Refer to Transmission Fluid Pump Disassemble (Overhaul) .
* Spacer plate and gaskets damaged or not assembled correctly
Refer to Control Valve Body and Spacer Plate Assemble (Overhaul) .
* Driven sprocket support seals damaged or missing
Refer to Driven Sprocket Support Assembly Removal (Overhaul) .
* Second clutch piston and seal assembly binding or damaged
* Second clutch fiber and steel plates not assembled correctly, burned, or damaged
* Second clutch spring assembly damaged or not assembled correctly
Refer to 2nd Clutch Disassemble (Overhaul) .
* Forward band burned, damaged, or not assembled correctly
Refer to 1-2 Support Drum and Forward Band Removal (Overhaul) .
* 1-2 support roller clutch assembly damaged or not assembled correctly
Refer to 1-2 Support Roller Clutch Disassemble (Overhaul) .

4. Using the scan tool, observe the shift times for the 2-3 upshift. The 2-3 shift time should be less than 0.65 second.

• If the 2-3 shift time is greater than 0.65 second, inspect and repair the following components:


* 2-3 accumulator piston seals rolled or damaged
* 2-3 accumulator piston and pin missing, binding, or damaged
Refer to Accumulator Components Disassemble (Overhaul) .
* Oil pump assembly damaged or missing components
Refer to Transmission Fluid Pump Disassemble (Overhaul) .
* Spacer plate and gaskets damaged or not assembled correctly
Refer to Control Valve Body and Spacer Plate Assemble (Overhaul) .
* Driven sprocket support seals damaged or missing
Refer to Driven Sprocket Support Assembly Removal (Overhaul) .
* Third clutch piston seal rolled or damaged
* Third clutch piston damaged or not assembled correctly
* Third clutch fiber and steel plates not assembled correctly, burned, or damaged
* Third clutch spring assembly damaged or not assembled correctly
Refer to Input and 3rd Clutch Disassemble (Overhaul) .
* Third sprag clutch assembly damaged or not assembled correctly
Refer to Input and 3rd Clutch Pawl Disassemble (Overhaul) .

5. Using the scan tool, observe the shift times for the 3-4 upshift. The 3-4 shift time should be less than 0.65 second.

• If the 3-4 shift time is greater than 0.65 second, inspect and repair the following components:


* Oil pump assembly damaged or missing components
Refer to Transmission Fluid Pump Disassemble (Overhaul) .
* Spacer plate and gaskets damaged or not assembled correctly
Refer to Control Valve Body and Spacer Plate Assemble (Overhaul) .
* 3-4 accumulator piston seals rolled or damaged
* 3-4 accumulator piston and pin missing, binding, or damaged
Refer to Case Assembly Inspection (Overhaul) .
* Fourth clutch piston seal rolled or damaged
* Fourth clutch piston damaged, not assembled correctly, or seized
Refer to Driven Sprocket Support Assembly Removal (Overhaul) .
* Fourth clutch fiber and steel plates not assembled correctly, burned, or damaged
Refer to 4th Clutch Components Removal (Overhaul) .
* Fourth clutch spring assembly damaged or not assembled correctly
Refer to Driven Sprocket Support Assembly Removal (Overhaul) .

6. Replace the automatic transmission fluid and filter. Add new automatic transmission fluid. Refer to Transmission Fluid Check (Testing and Inspection) .

• If the fluid is not at the proper level, add fluid as necessary.


Important: The Reset Transmission Adapts function will clear all adapt cells. This may affect transmission performance. The TCM will update the transmission adapt cell values as the vehicle is driven


7. Perform the Transmission Adapts function.



Component Testing

* Refer to Transmission Fluid Check (Testing and Inspection) .
* Refer to Line Pressure Check (Line Pressure Check Procedure) .
* Refer to Incorrect Line Pressure (Incorrect Line Pressure) .



Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.