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 P0972: Shift Solenoid (SS) 1 Control Circuit OpenDTC P0973: Shift Solenoid (SS) 1 Control Circuit Low Voltage
DTC P0974: Shift Solenoid (SS) 1 Control Circuit High Voltage
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Control | P0973 | P0972 | P0974 | -- |
Typical Scan Tool Data
Display Parameters | Normal Range | Short to Ground | Open/High Resistance | Short to Voltage |
|---|---|---|---|---|
Operating Conditions: Engine running, cycle gear shift selector through all ranges | ||||
Shift Solenoid 1 | On or Off | Off | Off | Off |
Circuit/System Description
Shift solenoid 1 (SS1) is a normally closed (N/C) solenoid that provides control main pressure to stroke shift valve 1. The transmission control module (TCM) determines the proper solenoid command logic to move shift valve 1 to attain a particular range. The TCM provides B+ to pressure control solenoid 2 (PCS2), and shift solenoids 1, 2, and 3 (SS1, SS2, and SS3) through a separate solid state device called high side driver 2 (HSD2). The TCM uses a low side driver to switch SS1 ON and OFF. Since the shift valve position is critical in determining the correct transmission range, a pressure switch located in the pressure switch manifold provides feedback to the TCM on the position of the valve.
Conditions for Running the DTC
P0972-P0974
| • | Ignition is ON. |
| • | Battery voltage is greater than 9.0 V and less than 18 V. |
| • | Engine running for greater than 5 seconds. |
Conditions for Setting the DTC
P0972
This DTC sets when the TCM detects an open circuit on the SS1 control circuit for greater than 1 second.
P0973
This DTC sets when the TCM detects a short to ground on the SS1 control circuit for greater than 1 second.
P0974
This DTC sets when the TCM detects a short to voltage on the SS1 circuit for greater than 1 second.
Action Taken When the DTC Sets
P0972-P0974
| • | The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL). |
| • | If the fault occurs while in a forward range, a shift to 1st, 3rd, or 5th range is made. |
| • | While diagnostic response is active, if the shift selector is moved to NEUTRAL, the transmission will shift to NEUTRAL. If the shift selector is moved to REVERSE, the transmission will shift to REVERSE. If the shift selector is moved to a forward range or to REVERSE and the transmission is compromised by overspeeding or direction change, the transmission will shift to NEUTRAL. |
| • | DTC P0972, P0973, or P0974 is stored in TCM history. |
| • | Main modulation (MAIN MOD) is inhibited. |
| • | The TCM freezes shift adapts. |
| • | The TCM inhibits torque converter clutch (TCC) engagement. |
Conditions for Clearing the DTC
DTCs P0972, P0973, and P0974 are Type A DTCs.
Diagnostic Aids
P0972
| • | You may have to drive the vehicle in order to experience a condition. |
| • | DTC P0972, set in combination with DTC P0964, P0975, and P0979, may indicate an open in the actuator supply voltage 2 circuits. |
P0973 and P0974
You may have to drive the vehicle in order to experience a condition.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Description and Operation
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 Verification
- Ignition ON, engine OFF, command the Shift Solenoid 1 ON and OFF with a scan tool. Observe the operation of the Shift Solenoid 1 parameter. The Shift Solenoid 1 parameter should turn On and Off.
- 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
- Ignition OFF, disconnect the X175 harness connector at the transmission.
- Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal N and ground.
- Connect a test lamp between the control circuit terminal A and the B+ circuit terminal N.
- Command the Shift Solenoid 1 ON and OFF with a scan tool and verify the Shift Solenoid 1 parameter changes from On to Off. The test lamp should turn ON and OFF when changing between the commanded states.
- Remove the transmission oil pan. Refer to Oil Pan Replacement.
- Test the transmission internal SS1, B+, and control circuits for a short to voltage, short to ground, or an open/high resistance.
| ⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the TCM. |
| ⇒ | If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the TCM. |
| ⇒ | If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the TCM. |
| ⇒ | If the circuits test normal, test or replace the SS1 solenoid. |
Component Testing
Static Testing
- Ignition OFF, remove the SS1 from the valve body. Refer to Control Valve Solenoid Replacement.
- Test for resistance between the control circuit terminal B, and the B+ circuit terminal A of the SS1. Refer to Temperature Versus Resistance.
Note: You must perform the Circuit/System Testing first.
| ⇒ | If not within the specified range, replace the SS1. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for TCM replacement, setup, and programming |
Repair Verification
If another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.
