GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2007 🢒 Vibe - FWD 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC P0974

Circuit Description

The shift solenoid valve #1 is located in the control valve body of the transmission. The powertrain control module (PCM) selects the required gear by turning the appropriate solenoid ON or OFF, enabling the transmission to shift.

Shifting from 1st to overdrive (O/D) is performed in combination with the PCM controlling the ON and OFF switching functions of the shift solenoids. If an open or short to ground occurs in either of the solenoid valves, the PCM controls the remaining functioning shift solenoid valve to allow the vehicle to be operated smoothly in a fail safe mode.

When the PCM detects a continuous open circuit in the shift solenoid valve #1 circuit, then DTC P0974 sets. DTC P0974 is a type B DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0974 Shift Solenoid (SS) Control Circuit High Voltage

Condition for Running the DTC

PCM detects an open circuit in shift solenoid #1 circuit 4 times.

Conditions for Setting the DTC

DTC P0974 sets when either of the following condition occurs:

The PCM detects an open in the shift solenoid #1 circuit when the solenoid is commanded OFF.

Action Taken When the DTC Sets
    • At the time of the first failure, the PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as a Failure Record.
    • The PCM illuminates the malfunction indicator lamp (MIL) during the first consecutive drive trip in which the Conditions for Setting the DTC are met.
    • The PCM turns OFF power to all solenoids, when the solenoids are OFF.
    • The PCM stores DTC P0974 in PCM history.

Conditions for Clearing the MIL/DTC
    • A scan tool can clear the MIL/DTC.
    • The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.

Test Description

The number below refers to the step number on the diagnostic table.

  1. Listen for an audible click when the solenoid energizes.

DTC P0974

Step

Action

Yes

No

Schematic Reference: Automatic Transmission Controls Schematics

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition with the engine OFF.

    3. Important: 

       • Before clearing the DTC, use the scan tool in order to record the PCM Freeze Frame Failure Records. Using the Clear Info function erases the Freeze Frame Failure Records from the powertrain control module (PCM).
       • Using the Clear Info function erases stored DTCs in the PCM.

  3. Record the DTC Freeze Frame and Failure Records.
  4. Clear the DTC.
  5. Use the scan tool in order to command the shift solenoid ON.

Does the solenoid operate?

Go to Step 5

Go to Step 3

3
  1. Turn OFF the ignition.
  2. Disconnect the PCM.
  3. Test the circuit from the PCM to the shift solenoid for an open circuit. Refer to Testing for Short to Ground .

Did you find a condition?

Go to Step 6

Go to Step 5

4
  1. Remove the transmission oil pan.
  2. Test the shift solenoid wiring from the 6-way connector to the shift solenoid connector for the following condition:

    3. Open circuit--Refer to Testing for Short to Ground .

Did you find a condition?

Go to Step 7

Go to Step 8

5

Replace the PCM. Refer to Powertrain Control Module Programming and Setup .

Is the action complete?

Go to Step 9

--

6

Perform the necessary wiring repairs. Refer to Wiring Repairs .

Is the action complete?

Go to Step 9

--

7

Replace the AT internal transmission wiring harness. Refer to Solenoids and Wiring Harness Replacement .

Is the action complete?

Go to Step 9

--

8

Replace the shift solenoid valve. Refer to Solenoids and Wiring Harness Replacement .

Is the action complete?

Go to Step 9

--

9

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear Info.
  3. Turn ON the ignition, with the engine OFF.
  4. Select Specific DTC.
  5. Enter DTC P0974.

Has the test run and passed?

Go to Step 10

Go to Step 2

10

With the scan tool, observe the stored information, capture info and DTC info.

Does the scan tool display any DTCs that you have not diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK