6T70/6T75 - Automatic Transmission
DTC P0969-P0971
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC P0969
- Clutch Pressure Control (PC) Solenoid 3 System Performance
DTC P0970
- Clutch Pressure Control (PC) Solenoid 3 Control Circuit Low Voltage
DTC P0971
- Clutch Pressure Control (PC) Solenoid 3 Control Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The clutch pressure (PC) solenoid 3 is part of the control solenoid valve assembly, which has no serviceable components. The normally high clutch PC solenoid 3 regulates and directs the clutch PC solenoid 3 oil pressure to the R1/4-5-6 clutch regulator valve and 4-5-6 clutch boost valve. Increasing clutch PC solenoid 3 oil pressure increases oil pressure to the low and reverse clutch or the 4-5-6 clutch, depending on the position of the clutch select valve 2. The TCM varies the current to the PC solenoid 3 through a low side driver. Decreasing the current to the clutch PC solenoid 3 increases clutch PC solenoid 3 oil pressure by closing OFF the solenoid exhaust port. Increasing the current to the clutch PC solenoid 3, decreases clutch PC solenoid 3 oil pressure by opening the solenoid exhaust port. Clutch PC solenoid 3 power is supplied by the TCM through a high side driver (HSD). The HSD protects the circuit and components from excessive current flow. If excessive current flow is detected, the HSD will turn OFF. When the fault is corrected the HSD will reset.
Conditions for Running the DTC
P0969
* The engine speed is greater than 400 RPM for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
* DTC P0969 has not set this ignition cycle.
P0970
* The engine speed is greater than 400 RPM for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
* DTC P0970 has not set this ignition cycle.
P0971
* The engine speed is greater than 400 RPM for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
* DTC P0971 has not set this ignition cycle.
Conditions for Setting the DTC
P0969
The TCM detects an internal electrical performance malfunction of the clutch PC solenoid 3 control circuit where the measured clutch PC solenoid 3 currents does not equal the commanded clutch PC solenoid 3 current for 5 seconds.
P0970
The TCM detects a short to ground on the clutch PC solenoid 3 control circuit for 1 second.
P0971
The TCM detects an open or short to voltage on the clutch PC solenoid 3 control circuit for 1 second.
Action Taken When the DTC Sets
P0969
* DTC P0969 is a Type C DTC.
* The TCM freezes transmission adaptive functions to the low and reverse clutch and 4-5-6 clutch.
P0970 or P0971
* DTCs P0970 and P0971 are Type A DTCs.
* The TCM limits the transmission to reverse and 5th gear.
* The TCM inhibits torque converter clutch (TCC).
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.
* The TCM turns the high side driver off.
* The TCM inhibits manual shifting of forward gears.
Conditions for Clearing the DTC
* DTC P0969 is a Type C DTC.
* DTCs P0970 and P0971 are Type A DTCs.
Reference Information
Connector End View Reference
* Component Connector End Views (Connector End Views By Name)
* Inline Harness Connector End Views (Connector End Views By Number)
Description and Operation
Transmission General Description (Transmission General Description)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Special Tools
DT-47825-20 Adapter Harness
Circuit/System Verification
1. Operate the vehicle in second gear long enough to ensure at least a 3°C (5°F) rise in TCM temperature, then operate the vehicle in Park for 5 seconds.
2. Operate the vehicle in drive range. Allow the transmission to shift through all forward gear ranges. Verify with a scan tool the following test status parameters display OK:
* PC Sol. 3 Perf. Test Status
* PC Sol. 3 Ckt. High Voltage Test Status
* PC Sol. 3 Ckt. Low Voltage Test Status
3. Operate the vehicle within the Conditions 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
Note: You must perform the Circuit/System Verification first.
1. Ignition OFF, remove the control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6T70/6T75 - Automatic Transmission).
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection).
3. Place the control solenoid valve assembly on a clean work surface near the transmission assembly.
4. Connect DT-47825-20 - jumper harness between the vehicle wire harness electrical connector, and the control solenoid valve assembly electrical connector.
5. Ignition ON, verify with a scan tool the following test status parameters display OK:
* PC Sol. 3 Perf. Test Status
* PC Sol. 3 Ckt. High Voltage Test Status
* PC Sol. 3 Ckt. Low Voltage Test Status
• If any test status parameter displays Fault or Malfunction, replace the control solenoid valve assembly.
Repair Instructions
Important:
* Perform the Service Fast Learn Adapts (Service Fast Learn Adapts) following all transmission related repairs.
* Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection).
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for control solenoid valve assembly replacement, setup, and programming