P0974
DTC P0973 or P0974
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach. Initial Inspection and Diagnostic Overview
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC P0973
Shift Solenoid (SS) 1 Control Circuit Low Voltage
DTC P0974
Shift Solenoid (SS) 1 Control Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Shift Solenoid (SS) 1:
Circuit/System Description
The shift solenoid (SS) 1 is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The control solenoid (w/body and TCM) valve assembly supplies 12 volts to SS 1 on the high side driver 2 circuit. The control solenoid (w/body and TCM) valve assembly controls the normally closed SS 1 on the SS 1 control circuit. The SS 1 controls the transmission fluid to the Mode-2 valve. In the OFF position no oil is supplied to the clutch pressure control (PC) solenoid 3 or the transmission fluid pressure (TFP) switch 5, and the 4-5-6 clutch is fed by drive fluid. In the ON position, Reverse fluid is allowed to flow and is supplied to the 3-5-R clutch.
Conditions for Running the DTC
* The engine run time is greater than 5 seconds.
* The SS 1 is commanded ON or OFF.
Conditions for Setting the DTC
P0973
The control solenoid (w/body and TCM) valve assembly detects an internal low voltage electrical malfunction of the SS 1 control circuit when the SS 1 is commanded OFF for 300 milliseconds.
P0974
The control solenoid (w/body and TCM) valve assembly detects an internal high voltage electrical malfunction of the SS 1 control circuit when the SS 1 is commanded ON for 300 milliseconds.
Action Taken When the DTC Sets
* DTCs P0973 and P0974 are Type A DTCs.
* The TCM defaults the transmission to 3rd gear if the current gear is 1st, 2nd, or 3rd, or 5th gear if the current gear is 4th, 5th, or 6th gear.
* The TCM inhibits the torque converter clutch (TCC).
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.
Conditions for Clearing the DIC/DTC
DTCs P0973 and P0974 are Type A DTCs.
Diagnostic Aids
When attempting to set solenoid electrical DTCs, ensure the control solenoid (w/body and TCM) valve assembly is warmed up and the transmission is operated in 2nd gear long enough to ensure a 3°C (5°F) increase in TCM temperature. This will place the TCM under the optimal conditions to test solenoid electrical DTCs.
Circuit/System Testing
1. Ensure the transmission fluid temperature is between 50-80°C (122-176°F).
2. Operate the vehicle in 2nd gear long enough to ensure at least a 3°C (5°F) rise in TCM temperature.
3. Place the gear selector in Reverse for 5 seconds and then idle vehicle for 5 seconds.
4. Observe the scan tool data parameter Shift Sol. 1 CKT Status. The parameter should display OK.
^ If the parameter displays Open, Short to Volts, Short to GND, or if the DTC resets, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection. Control Solenoid Valve and Transmission Control Module Assembly Inspection
^ If no concerns are found during the inspection, replace the control solenoid (w/body and TCM) valve assembly.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
Perform the Service Fast Learn Adapts. Programming and Relearning