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For 1990-2009 cars only
Makes 🢒 Holden 🢒 2009 🢒 WM Sedan 🢒 DTC 🢒 DTC P0756

Circuit Description

The 2-3 shift solenoid (SS) valve controls the fluid flow acting on the 2-3 shift valves. The 2-3 SS valve is a normally-open exhaust valve that is used with the 1-2 SS valve, in order to allow 4 different shifting combinations.

When the transmission control module (TCM) detects a 4-3-3-4 shift pattern, then DTC P0756 sets. DTC P0756 is a type A DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0756 2-3 Shift Solenoid (SS) Valve Performance - No First or Second Gear.

Conditions for Running the DTC
    • No throttle position (TP) sensor DTC P0120.
    • No output shaft speed (OSS) DTCs P0722 or P0723.
    • No torque converter clutch (TCC) performance DTC P0742.
    • No shift solenoid electrical DTCs P0973, P0974, P0976, or P0977.
    • No IMS DTCs P1815, P1820, P1822, P1823, P1825 or P1826.
    • The engine torque is between 108 N·m (80 lb ft) and 882 N·m (651 lb ft).
    • The engine run time is greater than 5 seconds.
    • The transmission fluid temperature is 20-130°C (68-266°F).
    • The throttle position is greater than 10 percent.
    • The output shaft speed is greater than 150 RPM.

Conditions for Setting the DTC

Both of the following conditions must occur twice during the same trip:

    • Fail Case 1: The TCM commands 1st gear when the output shaft speed is 200 RPM or greater, the engine torque is 40-350 N·m (30-258 lb ft), and the resulting gear ratio is 0.73:1-0.77:1 for 2.8 seconds.
    • Fail Case 2: The TCM commands 2nd gear when the engine torque is 36-350 N·m (27-258 lb ft) and the resulting gear ratio is 1.56:1-1.64:1 for 1 second.

Action Taken When the DTC Sets
    • The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • The TCM inhibits 1st gear.
    • The TCM commands maximum line pressure.
    • The TCM freezes transmission adaptive functions.
    • At the time of the first failure, the TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record.
    • At the time of the second failure, the ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as a Freeze Frame.
    • The TCM stores DTC P0756 in TCM history.

Conditions for Clearing the DTC
    • The ECM turns OFF the MIL after the 4th consecutive drive trip in which the TCM does not send a MIL illumination request.
    • A scan tool can clear the DTC.
    • The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.
    • The TCM cancels the DTC default actions when the ignition is OFF long enough in order to power down the TCM.

Diagnostic Aids
    • If you clear DTC P0756, and then cannot reset DTC P0756, the following conditions may exist:
       - Fluid contamination.
       - Plugged fluid circuits.
       - Restricted fluid circuits.
    • Refer to Shift Solenoid Valve State and Gear Ratio .

Test Description

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

  1. This step tests that the TCM commanded all shifts, that all shift solenoid valves responded correctly, but that all the shifts did not occur.

DTC P0756

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

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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 Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the transmission control module (TCM).

  3. Record the DTC Freeze Frame and Failure Records.
  4. Clear the DTC.
  5. Drive the vehicle in D4 range under the following conditions:

    6. Accelerate the vehicle, ensuring that the TCM commands 1st, 2nd, 3rd and 4th gears.

Did you detect a 4-3-3-4 shift pattern?

--

Go to Step 3

Go to Diagnostic Aids

3
  1. Inspect the shift solenoid/hydraulic circuit for the following conditions:
    2. • Debris or chips in the AFL oil passage.
    • Debris or chips restricting oil flow in passage #29 of the case or through the spacer plate gasket into the valve body.
    • A cracked 2-3 shift solenoid.
    • A 2-3 shift valve which is stuck or hung up in the valve body bore.
    • A 2-3 shuttle valve which is stuck or hung up in its bore.
    • Damaged seals on the shift solenoid valves--Refer to Shift Solenoid Leak Test .
  2. Clean and inspect the related valves, bores and the valve body for debris or contamination.

Did you find and correct the condition?

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Go to Step 4

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4

Perform the following procedure in order to verify the repair:

  1. Select DTC.
  2. Select Clear Info.
  3. Drive the vehicle in D4 range under the following conditions, only if traffic and road conditions permit:

    4. Hold the throttle at 40 percent and accelerate to 64 km/h (40 mph).

  4. Select Specific DTC.
  5. Enter DTC P0756.

Has the test run and passed?

--

Go to Step 5

Go to Step 2

5

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