Hummer H2. Manual — part 2434

z

The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an
emission-related diagnostic fault occurring.

z

The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power
down the PCM.

Diagnostic Aids

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Verify that the transmission meets the specifications in the Shift Speed table.

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Other internal transmission failures may cause more than one shift to occur.

Refer to the Shift Solenoid Valve State and Gear Ratio table.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2: This step tests that the PCM commanded all shifts, that all shift solenoid valves responded correctly,
but that all the shifts did not occur.

DTC P0757

Step

Action

Value

(s)

Yes

No

1

Did you perform the Diagnostic System Check
- Engine Controls?

-

Go to Step 2

Go to Diagnostic

System Check -

Engine Controls in

Engine Controls - 6.0L

(LQ4)

2

1. Install a scan tool.

2. Turn ON the ignition, with the engine

OFF.

3. Record the DTC Freeze Frame and

Failure Records.

4. Clear the DTC.

5. Drive the vehicle in D4 range under the

following condition:

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
PCM.

-

2004 Hummer H2

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E Diagnosis (DTC P0218 To DTC P2771) - Hummer H2

DTC P0758

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

Did you detect a 1-2-2-1 shift pattern?

Go to Step 3

Go to Intermittent

Conditions in Engine

Controls - 6.0L (LQ4)

3

Inspect the shift solenoid/hydraulic circuit for
the following conditions:

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An internal malfunction

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Damaged seals on the shift solenoid
valve

Refer to Shift Solenoid Leak Test .

Did you find and correct the condition?

-

Go to Step 4

-

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 condition, only if traffic and
road conditions permit:

Hold the throttle at 15% and accelerate
to 80 km/h (55 mph).

4. Select Specific DTC.

5. Enter DTC P0757.

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 in

Engine Controls -

6.0L (LQ4)

System OK

2004 Hummer H2

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E Diagnosis (DTC P0218 To DTC P2771) - Hummer H2

Fig. 19: 2-3 Shift Solenoid (SS) Valve Diagram
Courtesy of GENERAL MOTORS CORP.

Circuit Description

The 2-3 shift solenoid (SS) valve controls the fluid flow acting on the 2-3 shift valves. The solenoid is a
normally-open exhaust valve. With the 1-2 SS valve, the 2-3 SS valve allows four different shifting
combinations. The solenoid attaches to the control valve body within the transmission. The 2-3 SS valve
receives ignition voltage through the Ignition 0 voltage circuit. The powertrain control module (PCM) controls
the solenoid by providing the ground path on the 2-3 SS valve control circuit.

When the PCM detects a continuous open, short to ground or short to power in the 2-3 SS valve circuit, then
DTC P0758 sets. DTC P0758 is a type A DTC.

Conditions for Running the DTC

2004 Hummer H2

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E Diagnosis (DTC P0218 To DTC P2771) - Hummer H2

z

The engine speed is greater than 450 RPM for 5 seconds.

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The engine is not in fuel cutoff.

Conditions for Setting the DTC

DTC P0758 sets if one of the following conditions occurs for 5 seconds:

Condition 1

The PCM commands the solenoid ON and the voltage feedback remains high, B+.

Condition 2

The PCM commands the solenoid OFF and the voltage feedback remains low, 0 volts.

Action Taken When the DTC Sets

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The PCM illuminates the malfunction indicator lamp (MIL).

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The PCM commands third gear only.

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The PCM commands maximum line pressure.

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The PCM inhibits TCC engagement.

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The PCM freezes transmission adapt functions.

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The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM
stores this information as Freeze Frame and Failure Records.

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The PCM stores DTC P0758 in PCM history.

Conditions for Clearing the MIL/DTC

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The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and
passes.

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A scan tool can clear the MIL/DTC.

z

The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an
emission-related diagnostic fault occurring.

z

The PCM cancels the DTC default actions when the fault no longer exists and/or the ignition switch is
OFF long enough in order to power down the PCM.

Diagnostic Aids

Refer to the Shift Solenoid Valve State and Gear Ratio table.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

4: This step tests the function of the 2-3 SS valve and the automatic transmission (AT) wiring harness

2004 Hummer H2

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E Diagnosis (DTC P0218 To DTC P2771) - Hummer H2