2010 Cadillac CTS Sedan AWD V6-3.0L Page 1777
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Verification
Note: If other DTCs are set, diagnose those DTCs first.
1. Engine idling in Park, with parking brake applied and drive wheels chocked.
2. Perform the Transmission Fluid Level and Condition Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing
and Inspection/Initial Inspection and Diagnostic Overview/Transmission Fluid Level and Condition Check) to verify correct fluid level and
condition.
3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning (See: Transmission and Drivetrain/Automatic
Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/Control Solenoid Valve and Transmission Control
Module Assembly Cleaning) to dislodge debris and free up the valves.
Note: Perform a scan tool snapshot, during the road test.
4. Perform the Road Test (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Initial Inspection and
Diagnostic Overview/Road Test). Verify the transmission operation performs as indicated in the road test instructions.
5. Review the scan tool snapshot transmission data parameters. Verify the engine and transmission data parameters display the correct values in
all forward gear ranges:
* Engine Speed
* Vehicle Speed
* Transmission ISS
* Transmission OSS
* Shift Solenoid Valve 1
* Gear Command
6. Operate the vehicle within the Condition for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the
conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
1. Perform the Line Pressure Check (See: Transmission and Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component
Tests and General Diagnostics/Line Pressure Check). Verify the transmission line pressures are within the specified ranges.
瀚慖f not within the specified ranges, refer to Fluid Pressure High or Low (See: Transmission and Drivetrain/Automatic
Transmission/Transaxle/Testing and Inspection/Symptom Related Diagnostic Procedures/Fluid Pressure High or Low).
2. Ignition OFF, remove the Q8 control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly
Replacement (See: Powertrain Management/Transmission Control Systems/Actuators and Solenoids - Transmission and
Drivetrain/Actuators and Solenoids - A/T/Shift Solenoid/Service and Repair).
3. Perform the Control Solenoid Valve and Transmission Control Module Assembly Solenoid Performance Test (See: Transmission and
Drivetrain/Automatic Transmission/Transaxle/Testing and Inspection/Component Tests and General Diagnostics/Control Solenoid Valve and
Transmission Control Module Assembly Solenoid Performance Test).
瀚慖f the Q8 control solenoid valve assembly does not pass the performance test, replace the Q8 control solenoid valve assembly.
4. Listed in the chart below, are conditions for each component that could set DTC P1751. Carefully inspect each component for that condition.
Repair or replace as necessary.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
