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 provides an overview of each diagnostic category. |
DTC Descriptor
DTC P0973: Shift Solenoid (SS) 1 Control Circuit Low VoltageDTC P0974: Shift Solenoid (SS) 1 Control Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Shift Solenoid (SS) 1 Control | P0973 | P0974 | P0974 | -- |
Typical Scan Tool Data
Circuit | Short to Ground | Open | Short to Voltage |
|---|---|---|---|
Operating Conditions: Engine running, normal operating temperature Parameter Normal Range: OK | |||
Shift Sol. 1 CKT Status | Short to GND | Open | Short to Volts |
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 1 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 hybrid low, 1-2 clutch boost valve assembly.
In the OFF position, SS 1 controls the transmission fluid to the following components:
| • | EVT 1 mode, oil is supplied to drive motors with generator 1 and 2 for cooling and the hybrid low, 1-2 clutch |
| • | EVT 2 mode, oil is supplied to drive motors with generator 1 and 2 for cooling and the hybrid direct 2-3-4 clutch |
In the ON position, SS 1 controls the transmission fluid to the following components:
| • | Gear 1, oil is supplied to the hybrid low, 1-2 clutch and the 1-3 clutch |
| • | Gear 2, oil is supplied to the hybrid low, 1-2 clutch and the hybrid direct 2-3-4 clutch |
| • | Gear 3, oil is supplied to the hybrid direct 2-3-4 clutch and the 1-3 clutch |
| • | Gear 4, oil is supplied to the hybrid direct 2-3-4 clutch and the 4th clutch |
Conditions for Running the DTC
| • | The engine run time is greater than 5 seconds. |
| • | The vehicle speed is less than 200 km/h (124 mph) for 5 seconds. |
| • | The system voltage is 11-18 volts. |
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 SS 1 is commanded OFF for 1 second.
P0974
The control solenoid (w/body and TCM) valve assembly detects an internal high voltage electrical malfunction of the SS 1 control circuit when SS 1 is commanded ON for 1 second.
Action Taken When the DTC Sets
| • | DTCs P0973 and P0974 are Type A DTCs. |
| • | The TCM defaults the transmission to EVT 1 or EVT 2 depending on vehicle speed. |
| • | The TCM commands maximum line pressure. |
| • | The TCM freezes transmission adaptive functions. |
Conditions for Clearing the 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 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.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information.
Circuit/System Testing
- Ensure the transmission fluid temperature is between 50 and 80°C (122 and 176°F).
- Operate the vehicle in M 1 long enough to ensure at least a 3°C (5°F) rise in TCM temperature.
- Place the gear selector in D for 5 seconds and then idle vehicle for 5 seconds.
- 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 . |
| ⇒ | 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.
Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.
