Hummer H1 (2006+). Manual - part 87

 

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Hummer H1 (2006+). Manual - part 87

 

 

OBD-192

On-Board Diagnostics

_____________________________________________

Conditions for Clearing the DTC

A scan tool can clear the code from TCM history. The TCM automatically clears the DTC from TCM history if the vehicle com-
pletes 40 warm-up cycles without failure.

Diagnostic Aids 

• Inspect for aftermarket devices that could affect the operation of the starting and charging systems. 

• Inspect for the presence of aftermarket accessories, such as a remote starter, etc. Depending on how these aftermarket acces-

sories are installed, they may interfere with the required voltage for proper operation of the transmission. 

• Inspect the wiring for poor electrical connections at the TCM. Inspect for the following conditions: 

•  A bent terminal 

•  A backed-out terminal 

•  A damaged terminal 

•  Poor terminal tension 

•  A chafed wire 

•  A broken wire inside the insulation 

• When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a 

change.

• You may have to drive the vehicle in order to experience a condition. 

Step

Action

Value(s)

Yes

No

    1

NOTE: Before clearing DTC(s) use the scan tool “Capture info”
to record Freeze Frame and Failure Records for reference, as data
will be lost when “Clear Info” function is used 

Was the “On-Board Diagnostic (OBD) System Check” per-
formed?

Go to step 2.

Go to OBD Sys-

tem Check.

    2

1.

Install the scan tool.

2.

Turn ON the ignition, with the engine OFF.

NOTE: Before clearing the DTC, use the scan tool in order to
record the Freeze Frame and Failure Records for reference. The
Clear Info function will erase the data.

3.

Record the DTC Freeze Frame and Failure Records.

4.

Clear the DTC.

5.

Start the engine and observe the charge indicator on the 
instrument panel cluster (IPC).

Does the charge indicator illuminate or the driver information
center (DIC) display a charging system message?

Go to Charging 

System Test in 

Engine Electri-

cal

Go to Step 3 

    3

1.

Turn the ignition OFF.

2.

Disconnect the TCM C78 at the TCM.

3.

Install the J 39700 breakout box and the J 43799 breakout 
box adapter at the C78.

4.

Using a DVOM, measure voltage at the +12v Battery input 
CKT 1037 (RD) between C78 pin 3, and a good ground.

Is voltage within the specified value?

B+

Go to Step 4

Go to Step 5

_____________________________________________

 On-Board Diagnostics  OBD-193

5745804

    4

Using a DVOM, in sequence, measure the voltage from the 12
volt ignition voltage circuits 243 (PK) at C78 pin 2, and C78 pin
4, and a good ground.

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

Is voltage within the specified value?

B+

Go to Step 7

Go to Step 6

    5

Test the battery positive voltage circuit 1037 (RD) for an open or
short to ground between C78 pin 3 and fuse 2B in the external
fuse box. 

Did you find and correct the condition?

Go to Step 10 

Go to Diagnos-

tic Aids

    6

Test the ignition feed circuit 1037 (RD) for an open or short to
ground between C78 pin 2 and fuse 1D and also between C78 pin
4 and fuse 1Din the external fuse box.

Did you find and correct the condition?

Go to Step 10 

Go to Step 9 

    7

1.

Start the engine.

2.

Operate all accessories. 

Did voltage fluctuate by the specified value?

4 Volts

Go to Step 8

Go to Step 9 

    8

Determine the cause of the accessory voltage drop.

Did you find and correct the condition?

Go to Step 10 

Go to Diagnos-

tic Aids

    9

NOTE: In most cases, the TCM is not at fault. Investigate thor-
oughly before replacing the TCM.

Replace the faulty TCM. 

Did you complete the replacement?

Go to Step 10 

   10

Perform the following procedure in order to verify the repair:

1.

Clear the DTC.

2.

Using the scan tool, monitor TCM voltage.

3.

Select Specific DTC.

4.

Enter DTC P0561.

Has the test run and passed?

System OK

Go to Step 1

Step

Action

Value(s)

Yes

No

OBD-194

On-Board Diagnostics

_____________________________________________

DTC P0562 System Voltage Low

Circuit Description

The transmission control module (TCM) requires a switched ignition voltage to operate. The voltage signal should be direct from
the ignition switch to avoid any interference.

DTC P0562 is a type C DTC.

Conditions for Setting the DTC

DTC P0562 sets when the TCM detects ignition voltage below 8.0 volts at 0°C (32°F) for a total of 5 out of 7 seconds. The voltage
threshold is temperature dependant, varying from 5.0 volts at -60°C (-76°F) to 9.0 volts at 20°C (68°F).

Action Taken When the DTC Sets 

•   The TCM does not illuminate the malfunction indicator lamp (MIL). 

•   The transmission fails to hydraulic default. 

•   DTC P0562 will be stored in TCM history. 

•   The TCM inhibits torque converter clutch (TCC) engagement. 

•   The TCM freezes shift adapts. 

Conditions for Clearing the DTC

A scan tool can clear the code from TCM history. The TCM automatically clears the DTC from TCM history if the vehicle com-
pletes 40 warm-up cycles without failure.

Diagnostic Aids 

•   Inspect for the presence of aftermarket accessories, such as a remote starter, etc. Depending on how these aftermarket ac-

cessories are installed, they may interfere with the required voltage for proper operation of the transmission. 

•   Inspect the wiring for poor electrical connections at the TCM. Inspect for the following conditions: 

•   A bent terminal 

•   A backed-out terminal 

•   A damaged terminal 

•   Poor terminal tension 

•   A chafed wire 

•   A broken wire inside the insulation 

•   When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a 

change.

•   You may have to drive the vehicle in order to experience a condition. 

Step

Action

Value(s)

Yes

No

    1

NOTE: Before clearing DTC(s) use the scan tool “Capture info”
to record Freeze Frame and Failure Records for reference, as data
will be lost when “Clear Info” function is used 

Was the “On-Board Diagnostic (OBD) System Check” per-
formed?

Go to step 2.

Go to OBD Sys-

tem Check.

_____________________________________________

 On-Board Diagnostics  OBD-195

5745804

    2

1.

Install the scan tool.

2.

Turn ON the ignition, with the engine OFF.

NOTE: Before clearing the DTC, use the scan tool in order to
record the Freeze Frame and Failure Records for reference. The
Clear Info function will erase the data.

3.

Record the DTC Freeze Frame and Failure Records.

4.

Clear the DTC.

5.

Using a DVOM, measure and record voltage at the battery 
terminals.

Is voltage within the specified value?

B+

Go to Step 3

Go to Step 4

    3

Start the engine and observe the charge indicator on the instru-
ment cluster.

Does the charge indicator illuminate?

Go to Step 5

Go to Step 6

    4

Replace the battery or resolve the battery condition. 

Did you resolve the condition or complete the replacement?

Go to Step 6

    5

Repair the charging system. 

Did you complete the repair?

Go to Step 6

    6

Perform the following procedure in order to verify the repair:

1.

Clear the DTC.

2.

Using the scan tool, monitor TCM voltage.

3.

Select Specific DTC.

4.

Enter DTC P0562.

Has the test run and passed?

System OK

Go to Step 1

Step

Action

Value(s)

Yes

No

 

 

 

 

 

 

 

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