Hummer H2. Manual - part 2446

downshift" appears on the scan tool display.  

{

The gear requested may not be greater than the current 
selected transmission range (PRNDL). For example, 3rd 
gear is not allowed if the transmission range is D2. If the 
gear requested is greater than the current selected 
transmission range, the message "Eng. running and gear 
request is greater than the current TR" appears on the scan 
tool display.  

{

The solenoid remains ON until commanded OFF, and vice 
versa. When the output control is exited, the solenoid state 
is determined by the PCM.  

3-2 Downshift 
Solenoid

-

z

The PCM commands the 3-2 shift solenoid valve ON and OFF. 
The scan tool 3-2 Downshift Sol. parameter should match the 
commanded state.  

z

When the ignition is ON, and the engine is OFF, there are no 
limits to this control. The solenoid remains ON until commanded 
OFF, and vice versa. When the output control is exited, the 
solenoid state is determined by the PCM.  

z

When the engine is running, the following control limits apply: 

{

The transmission range (PRNDL) must be in Park or 
Neutral. If the transmission range is not in Park or Neutral, 
the message "Engine running and transmission range is not 
Park/Neutral" appears on the scan tool display.  

{

The solenoid remains ON until commanded OFF, and vice 
versa. When the output control is exited, the solenoid state 
is determined by the PCM.  

Clear TAP 
(Transmission 
Adaptive 
Pressures)

-

z

The PCM clears, or resets, the TAP cells to the original base 
value.  

z

There are no limits to using this output control. It may be 
performed with the engine running or when the ignition is ON, 
and the engine is OFF.  

z

The PCM commands the amperage, current, to the pressure 
control solenoid in order to control transmission line pressure. As 
the amperage increases, the line pressure decreases. As the 
amperage decreases, the line pressure increases. The amperage 
range is 0.00-1.10 and may be commanded in one-tenth amp 
increments.  

z

When the ignition is ON, and the engine is OFF, the reference, 
commanded, amperage may be controlled within calibrated limits. 
The scan tool parameter "PC Sol. Ref. Current" changes but the 
parameter "PC Sol. Actual Current" does not change. The 
reference current remains until commanded otherwise.  

z

When the engine is running, the following control limits apply: 

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle, 4L60-E/4L65-E (Diagnostic Information & Procedures) - Hummer H2

  

PC Solenoid

-

{

When the transmission range is Park or Neutral, the 
reference, commanded, amperage may be controlled within 
calibrated limits. The engine speed must be less than 1,500 
RPM. If the engine speed is greater than 1,500 RPM, the 
message "TR in park/neutral and engine speed over 1,500 
RPM" appears on the scan tool display. Both the scan tool 
parameters "PC Sol. Ref. Current" and "PC Sol. Actual 
Current" change. Both current readings remain until 
commanded otherwise.  

{

When the transmission range is not in Park or Neutral, the 
reference amperage can only be controlled less than the 
current determined by the PCM. The PCM does not allow a 
value to be selected that may cause damage to the 
transmission. If the requested amperage is more than 
allowed by the PCM, the message "Requested current for 
the PC Solenoid is too high" appears on the scan tool 
display.  

{

Transmission range DTCs must not be active. If a 
transmission range DTC is active, the message "Engine 
running with transmission DTC present" appears on the 
scan tool display.  

Shift 
Transmission

-

z

The PCM commands upshifts and downshifts. The scan tool 
Commanded Gear parameter should correspond with the shift 
solenoid combination. Refer to Shift Solenoid Valve State and 
Gear Ratio table.  

z

When the ignition is ON, and the engine is OFF, there are no 
limits to this control. The scan tool shift solenoid states change to 
match the Commanded Gear selected.  

z

When the engine is running, the following control limits apply: 

{

The PCM does not allow a shift if it causes the engine RPM 
to exceed a calibrated limit. If a gear is requested and the 
engine speed is too high, the message "Engine speed too 
high" appears on the scan tool display.  

{

The PCM does not allow a 3-2 or 2-1 downshift if the 
vehicle speed exceeds a calibrated limit. If either downshift 
is requested and the vehicle speed is too high, the message 
"Eng. is on and veh. speed too hi for 3-2 or 2-1 downshift" 
appears on the scan tool display.  

{

The PCM does not allow a 4-3 downshift if the vehicle 
speed exceeds a calibrated limit. If a 4-3 downshift is 
requested and the vehicle speed is too high, the message 
"Vehicle speed too high" appears on the scan tool display.  

{

The PCM does not allow an upshift if the vehicle speed 
exceeds a calibrated limit. If an upshift is requested and the 

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle, 4L60-E/4L65-E (Diagnostic Information & Procedures) - Hummer H2

  

SCAN TOOL DATA LIST 

Use the scan tool data list under the following conditions: 

z

The Diagnostic System Check - Automatic Transmission is complete.  

z

The on-board diagnostics are functioning properly.  

z

No DTCs are present.  

The values below represent a typical display recorded from a properly functioning system. 

Only the parameters listed below are used in this manual for diagnosing. If a scan tool displays other 
parameters, the values are not recommended by General Motors for use in diagnosis. 

vehicle speed is too high, the message "Vehicle speed too 
high" appears on the scan tool display.  

{

The PCM does not allow an upshift that is greater than the 
current selected transmission range (PRNDL). For example 
3rd gear is not allowed if the transmission range is D2. If an 
upshift is requested that is greater than the current selected 
transmission range, the message "Eng. running and gear 
request is greater than the current TR" appears on the scan 
tool display.  

TCC Control 
Solenoid

-

z

The PCM commands the duty cycle of the TCC PWM solenoid. 
The duty cycle is represented by a percentage of ON, energized, 
time. Approximately 90-100 percent duty cycle represents an ON, 
energized, commanded state. Zero percent represents an OFF, 
non-energized, commanded state. The scan tool TCC Duty Cycle 
parameter should match the commanded state.  

z

When the ignition is ON, and the engine is OFF, there are no 
limits to this control. The solenoid remains ON, 90-100 percent 
duty cycle, until commanded OFF, zero percent duty cycle, and 
vice versa. When the output control is exited, the solenoid duty 
cycle is determined by the PCM.  

TCC Enable

-

z

The PCM commands the TCC enable solenoid valve ON and 
OFF. The scan tool TCC Enable parameter should match the 
commanded state.  

z

When the ignition is ON, and the engine is OFF, there are no 
limits to this control. The solenoid remains ON until commanded 
OFF, and vice versa. When the output control is exited, the 
solenoid state is determined by the PCM.  

IMPORTANT: Do not use a scan tool that displays faulty data. Report the condition to the 

scan tool manufacturer. The use of a faulty scan tool can result in 
misdiagnosis and the unnecessary replacement of parts.

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle, 4L60-E/4L65-E (Diagnostic Information & Procedures) - Hummer H2

  

Scan tool values below were recorded under the following conditions:

z

Engine at idle  

z

Upper radiator hose hot  

z

Closed throttle  

z

Transmission in PARK  

z

Closed Loop operation  

z

Accessories OFF  

z

Brake pedal not applied  

Transmission Scan Tool Data List (N Truck) 

Scan Tool Parameter

Data List*

Units Displayed

Typical Data Value

1-2 Shift Error

F2, F7/F0

Seconds

Varies

1-2 Shift Time

F0, F2, F7/F0

Seconds

Varies

1-2 Sol.

F0, F2, F3, F4

On/Off

On

1-2 Sol. Open/Short to 
GND

F2

Yes/No

No

1-2 Sol. Short to Volts

F2

Yes/No

No

1-2 TAP Cell (4-16)

F7/F0

kPa/Psi

Varies

2-3 Shift Error

F3, F7/F1

Seconds

Varies

2-3 Shift Time

F0, F3, F7/F1

Seconds

Varies

2-3 Sol.

F0, F2, F3, F4

On/Off

On

2-3 Sol. Open/Short to 
GND

F3

Yes/No

No

2-3 Sol. Short to Volts

F3

Yes/No

No

2-3 TAP Cell (4-16)

F7/F1

kPa/Psi

Varies

3-2 Downshift Sol.

F0, F5

On/Off

On

3-2 Sol. Open/Short to 
GND

F5

Yes/No

No

3-2 Sol. Short to Volts

F5

Yes/No

No

3-4 Shift Error

F4

Seconds

Varies

3-4 Shift Time

F0, F4

Seconds

Varies

4WD

F0

Enabled/Disabled

Disabled

4WD Low

F0

Enabled/Disabled

Disabled

A/C Clutch

F0

On/Off

Off

Commanded Gear

F0, F1, F2, F3, 

F4, F5, F6

1, 2, 3, 4

1

Cruise

F0

Enabled/Disabled

Disabled

Current TAP Cell

F7/F0, F7/F1

4-16

Varies

ECT

F0, F1

°C (°F)

Varies

Engine Run Time

F0

Hr/Min/Sec

Varies

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transaxle, 4L60-E/4L65-E (Diagnostic Information & Procedures) - Hummer H2