Hummer H2. Manual — part 2499

DTC P2761

Fig. 23: Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid Valve Diagram
Courtesy of GENERAL MOTORS CORP.

Circuit Description

5. Enter DTC P1810.

Has the test run and passed?

Go to Step 17

Go to Step 2

17

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

The torque converter clutch pulse width modulation (TCC PWM) solenoid valve controls the fluid acting on the
converter clutch valve. The converter clutch valve controls the TCC application and release. The solenoid
attaches to the control valve body within the transmission. The solenoid receives ignition voltage through the
Ignition 0 voltage circuit. The powertrain control module (PCM) controls the solenoid by providing a ground
path on the TCC PWM solenoid valve control circuit. Current flows through the solenoid coil according to the
duty cycle, percentage of ON and OFF time. The TCC PWM solenoid valve provides a smooth engagement of
the TCC by operating during a duty cycle percent of ON time.

When the PCM detects a continuous open, short to ground or short to power in the TCC PWM solenoid valve
circuit, then DTC P2761 sets. DTC P2761 is a type B DTC.

Conditions for Running the DTC

z

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

z

The engine is not in fuel cutoff.

z

The PCM commands first gear.

z

The TCC duty cycle is less than 10 percent or greater than 90 percent.

Conditions for Setting the DTC

DTC P2761 sets if one of the following conditions occurs for 5 seconds:

Condition 1

The PCM commands the solenoid ON, 90 percent, and the voltage feedback remains high, B+.

Condition 2

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

Action Taken When the DTC Sets

z

The PCM illuminates the malfunction indicator lamp (MIL) during the second consecutive trip in which
the Conditions for Setting the DTC are met.

z

The PCM inhibits TCC engagement.

z

The PCM inhibits 4th gear if the transmission is in hot mode.

z

The PCM freezes transmission adapt functions.

z

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.

z

The PCM stores DTC P2761 in PCM history during the second consecutive trip in which the Conditions
for Setting the DTC are met.

Conditions for Clearing the MIL/DTC

z

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

2004 Hummer H2

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

passes.

z

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.

Test Description

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

4: This step tests for voltage to the solenoid.

5: This step tests the ability of the PCM and wiring to control the ground circuit.

7: This step tests the resistance of the TCC PWM solenoid valve and the automatic transmission wiring
harness assembly.

DTC P2761

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.

Are any of the following DTCs also set?

z

P0740

z

P0753

z

P0758

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

z

P0785

Go to Step 3

Go to Step 4

3

Inspect the IGN 0 fuse for an open.
Refer to Circuit Protection - Fuses in Wiring
Systems.
Is the fuse open?

-

Go to Step 11

Go to Step 4

4

1. Turn OFF the ignition.

2. Disconnect the AT inline 20-way connector,

additional DTCs may set.

3. Install the J 44152 Jumper Harness (20 pins) on

the engine side of the AT inline 20-way
connector.

4. Turn ON the ignition, with the engine OFF.

5. Using the J 35616 GM Terminal Test Kit,

connect a test lamp from terminal E of the J
44152 to ground.

Refer to Automatic Transmission Inline 20-
Way Connector End View .

Does the test lamp illuminate?

-

Go to Step 5

Go to Step 14

5

1. Connect the test lamp between terminal E and

terminal U of the J 44152 .

Refer to Automatic Transmission Inline 20-
Way Connector End View .

2. Use the scan tool in order to command the TCC

PWM solenoid valve ON and OFF three times.

Does the test lamp turn ON and OFF with each
command?

-

Go to Step 7

Go to Step 6

6

Is the test lamp always ON?

-

Go to Step 15

Go to Step 16

7

1. Install the J 44152 on the transmission side of

the AT inline 20-way connector.

2. Using the DMM and the J 35616 , measure the

resistance between terminal E and terminal U of
the J 44152 .

Refer to Automatic Transmission Inline 20-
Way Connector End View .

Does the resistance measure within the specified
range?

10-15

ohm

Go to Step 8

Go to Step 9

2004 Hummer H2

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