P0973
DTC P0973 or P0974
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 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
Circuit/System Description
The shift solenoid (SS) 1 is part of the control solenoid valve assembly, which has no serviceable components. SS 1 is a normally closed (NC) ON/OFF solenoid and is controlled by the transmission control module (TCM) through a low side driver. When the SS 1 is energized (ON), SS 1 fluid pressure is directed to the clutch select valve 2, which allows the valve to overcome the spring pressure and move to the applied position. Power to the SS 1 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
P0973
* Engine speed is 400 RPM or greater for 5 seconds.
* Ignition voltage is 8.6 volts or greater.
* DTC P0973 is not set.
P0974
* Engine speed is 400 RPM or greater for 5 seconds.
* Ignition voltage is 8.6 volts or greater.
* DTC P0974 is not set.
Conditions for Setting the DTC
P0973
TCM detects a short to ground on the SS 1 control circuit for 2 seconds.
P0974
TCM detects an open or a short to power on the SS 1 control circuit for 2 seconds.
Action Taken When the DTC Sets
P0973
* DTC P0973 is a Type A DTC.
* TCM limits the transmission to Reverse and 3rd gear operation.
* TCM commands maximum line pressure.
* TCM freezes transmission adaptive functions.
* TCM forces TCC OFF.
* TCM forces the HSD OFF.
* TCM inhibits neutral idle.
* TCM inhibits Tap Up/Down function.
* TCM inhibits manual shifting of forward gears.
P0974
* DTC P0974 is a Type B DTC.
* TCM inhibits 1st gear.
* TCM inhibits neutral idle.
Conditions for Clearing the DIC/DTC
* DTC P0973 is a Type A DTC.
* DTC P0974 is a Type B DTC.
Reference Information
Connector End View Reference
* Component Connector End Views A/C Compressor Clutch
* Inline Harness Connector End Views X101
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 Control Module References for scan tool information
Special Tools
DT-47825-20 - Adapter Harness
For equivalent regional tools, refer to Special Tools Tools and Equipment.
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. Place the gear selector in Reverse for 5 seconds and then idle the vehicle in Park for 5 seconds. Verify with a scan tool the following test status parameters display OK:
* Shift Sol. 1 Ctrl. Ckt. High Voltage Test Status
* Shift Sol. 1 Ctrl. Ckt. Open Test Status
* Shift Sol. 1 Ctrl. Ckt. Low Voltage Test Status
• If any test status parameter displays Fault or Malfunction
Refer to Circuit/System Testing below.
• If all test status parameters display OK
3. After performing the above steps, verify that the DTC does not reset by operating the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions you observe from the Freeze Frame/Failure Records data. If the vehicle passes the Circuit/System Verification procedure, then STOP. Do not perform the Circuit/System Testing or Component Testing as this may result in an unnecessary part replacement. Refer to Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections.
Circuit/System Testing
Note:
You must perform the Circuit/System Verification first.
1. Ignition OFF, remove the Q8 control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement Service and Repair.
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection Control Solenoid Valve and Transmission Control Module Assembly Inspection. The Q8 control solenoid valve and transmission control module assembly must be externally cleaned of all debris.
3. Place the Q8 control solenoid valve assembly on a clean work surface near the transmission assembly.
4. Connect the DT-47825-20 - harness between the vehicle wire harness X1 20-way transmission electrical connector, and the Q8 control solenoid valve assembly electrical connector.
5. Ignition ON, verify with a scan tool the following test status parameters display OK:
* Shift Sol. 1 Ctrl. Ckt. High Voltage Test Status
* Shift Sol. 1 Ctrl. Ckt. Open Test Status
* Shift Sol. 1 Ctrl. Ckt. Low Voltage Test Status
• If any test status parameter displays Fault or Malfunction
Replace the Q8 control solenoid valve assembly.
• If all test status parameters display OK
6. All OK.
Repair Instructions
Note:
* Perform the Reset Transmission Adapts Reset Transmission 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 Control Module References for control solenoid valve assembly replacement, setup, and programming