DTC P0973 or P0974 Hybrid

Diagnostic Instructions

DTC Descriptors

DTC P0973:  1-2 Shift Solenoid (SS) Control Circuit Low Voltage

DTC P0974:  1-2 Shift Solenoid (SS) Control Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage
Ignition 1 Voltage	P0973, P0976, P2764	P0973, P0976, P2764	--
1-2 SS Valve Control	P0973	P0973	P0974
2-3 SS Valve Control	P0976	P0976	P0977
TCC PWM Valve Control	P2764	P2764	P2763

Typical Scan Tool Data

1-2 Shift Solenoid (SS) Control Circuit Parameter Data

Circuit	Normal	Short to Ground	Open/High Resistance	Short to Voltage
Operating Conditions: Engine running, normal operating temperature Parameter Normal Range: OK
1-2 Sol. CKT Status	OK	Open/Short to GND	Open/Short to GND	Short to Volts
2-3 Sol. CKT Status	OK	Open/Short to GND	Open/Short to GND	Short to Volts
TCC Duty Cycle CKT Status	OK	Open/Short to GND	Open/Short to GND	Short to Volts

Circuit/System Description

The 1-2 shift solenoid (SS) valve and the 2-3 SS valves control transmission fluid pressure acting on the shift valves to position the valves for the appropriate gear. The 1-2 SS and the 2-3 SS valves are normally-open exhaust valves located on the control valve body. A fused circuit supplies ignition voltage to the 1-2 SS valve and the 2-3 SS valve. The transmission control module (TCM) commands the solenoid ON or OFF by switching the ground path. When the 1-2 SS valve or the 2-3 SS valve is commanded ON, the TCM senses low voltage. When the 1-2 SS valve or the 2-3 SS valve is commanded OFF, the TCM senses high voltage.

Conditions for Running the DTC

The engine speed is greater than 500 RPM for 2 seconds.

Conditions for Setting the DTC

P0973

The TCM detects an open or short to ground on the 1-2 SS valve control circuit for 4.4 seconds.

P0974

The TCM detects a short to voltage on the 1-2 SS valve control circuit for 4.4 seconds.

Action Taken When the DTC Sets

P0973

P0974

Conditions for Clearing the DTC

DTCs P0973 and P0974 are Type B DTCs.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Component Description for Shift Solenoid Valves 1-2 and 2-3 information

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 44152 Jumper Harness (20 pins)

Circuit/System Verification

1. Ignition ON, engine OFF, observe the 1-2 Sol. CKT Status parameter while commanding the 1-2 SS ON and OFF with a scan tool. The reading should display OK or Indeterminate.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Important: Additional DTCs may set when disconnecting the automatic transmission inline 20-way connector.

1. Ignition OFF, disconnect the automatic transmission (AT) inline 20-way connector at the transmission.
2. Install the J 44152 on the engine side of the AT inline 20-way connector.
3. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal E and ground.

⇒	If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all components connected to the ignition circuit and replace as necessary.

4. Connect a test lamp between the control circuit terminal A and the ignition circuit terminal E.
5. Command the 1-2 SS ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒	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.

6. If all circuits test normal, test the automatic transmission internal wiring harness and the 1-2 shift solenoid.

Component Testing

1. Ignition OFF, disconnect the automatic transmission (AT) inline 20-way connector at the transmission.
2. Install the J 44152 on the transmission side of the AT inline 20-way connector.
3. Test for 19-31 ohms of resistance between the control terminal A and the ignition terminal E of the transmission.

⇒	If not within the specified range, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted or open replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid.

4. Test for infinite resistance between each terminal and the transmission housing/case.

⇒	If not the specified value, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

DTC P0973 or P0974 Non-Hybrid

Diagnostic Instructions

DTC Descriptors

DTC P0973:  1-2 Shift Solenoid (SS) Control Circuit Low Voltage

DTC P0974:  1-2 Shift Solenoid (SS) Control Circuit High Voltage

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage
Ignition 1 Voltage	P0973, P0976, P2764	P0973, P0976, P2764	--
1-2 SS Valve Control	P0973	P0973	P0974
2-3 SS Valve Control	P0976	P0976	P0977
TCC PWM Valve Control	P2764	P2764	P2763

Typical Scan Tool Data

1-2 Shift Solenoid (SS) Control Circuit Parameter Data

Circuit	Normal	Short to Ground	Open/High Resistance	Short to Voltage
Operating Conditions: Engine running, normal operating temperature Parameter Normal Range: OK
1-2 Sol. CKT Status	OK	Open/Short to GND	Open/Short to GND	Short to Volts
2-3 Sol. CKT Status	OK	Open/Short to GND	Open/Short to GND	Short to Volts
TCC Duty Cycle CKT Status	OK	Open/Short to GND	Open/Short to GND	Short to Volts

Circuit/System Description

The 1-2 shift solenoid (SS) and the 2-3 SS valves control transmission fluid pressure acting on the shift valves to position the valves for the appropriate gear. The 1-2 SS and the 2-3 SS valves are normally-open exhaust valves located on the control valve body. A fused circuit supplies ignition voltage to the 1-2 SS valve and the 2-3 SS valve. The transmission control module (TCM) commands the solenoid ON or OFF by switching the ground path. When the 1-2 SS valve or the 2-3 SS valve is commanded ON, the TCM senses low voltage. When the 1-2 SS valve or the 2-3 SS valve is commanded OFF, the TCM senses high voltage.

Conditions for Running the DTC

The engine speed is greater than 500 RPM for 2 seconds.

Conditions for Setting the DTC

P0973

The TCM detects an open or short to ground on the 1-2 SS valve control circuit for 4.4 seconds.

P0974

The TCM detects a short to voltage on the 1-2 SS valve control circuit for 4.4 seconds.

Action Taken When the DTC Sets

P0973

P0974

Conditions for Clearing the DTC

DTCs P0973 and P0974 are Type B DTCs.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Electronic Component Description for Shift Solenoid Valves 1-2 and 2-3 information

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

J 44152 Jumper Harness (20 pins)

Circuit/System Verification

1. Ignition ON, engine OFF, observe the 1-2 Sol. CKT Status parameter while commanding the 1-2 SS ON and OFF with a scan tool. The reading should display OK or Indeterminate.
2. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

Important: Additional DTCs may set when disconnecting the automatic transmission inline 20-way connector.

1. Ignition OFF, disconnect the automatic transmission (AT) inline 20-way connector at the transmission.
2. Install the J 44152 on the engine side of the AT inline 20-way connector.
3. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal E and ground.

⇒	If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit tests normal and the ignition circuit fuse is open, test all components connected to the ignition circuit and replace as necessary.

4. Connect a test lamp between the control circuit terminal A and the ignition circuit terminal E.
5. Command the 2-3 SS ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

⇒	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.

6. If all circuits test normal, test the automatic transmission internal wiring harness and the 2-3 shift solenoid.

Component Testing

1. Ignition OFF, disconnect the automatic transmission (AT) inline 20-way connector at the transmission.
2. Install the J 44152 on the transmission side of the AT inline 20-way connector.
3. Test for 19-31 ohms of resistance between the control terminal A and the ignition terminal E of the transmission.

⇒	If not within the specified range, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted or open replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid.

4. Test for infinite resistance between each terminal and the transmission housing/case.

⇒	If not the specified value, test the circuits for a short to ground or an open/high resistance. If a circuit is shorted replace the internal transmission harness, if the circuits test normal, replace the 2-3 shift solenoid.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.