Hummer H2. Manual - part 2448

A/C Clutch  

Displays On or Off. This parameter indicates the commanded state of the A/C control relay. The clutch 
should be engaged when On displays. 

Commanded Gear  

Displays 1, 2, 3 or 4. This parameter indicates the current commanded gear. 

Cruise  

Displays Enabled or Disabled. This parameter indicates whether the PCM is allowing cruise operation. 
The PCM has the ability to disable cruise control under certain conditions. 

Current TAP Cell  

The Current Transmission Adaptive Pressure Cell parameter indicates the current TAP cell in use for 
transmission line pressure adaptation. The cells are based on engine torque. The higher the engine torque, 
the higher the current TAP cell. The last cell used will remain displayed until the next adaptable upshift 
occurs. 

ECT  

The Engine Coolant Temperature parameter is the input signal of the engine coolant temperature sensor. 
The engine coolant temperature is high 151°C (304°F) when the signal voltage is low, 0 V, and the 
engine coolant temperature is low -40°C (-40°F) when the signal voltage is high, 5 V. 

Engine Run Time  

This parameter measures how long the engine has been operating. When the ignition switch is turned 
OFF, the value is reset to zero. 

Engine Speed  

This parameter indicates the rotational speed of the engine expressed as revolutions per minute. 

Engine Torque  

This parameter indicates the amount of torque that is delivered from the engine. 

Estimated Gear Ratio  

This parameter indicates the estimated turbine speed divided by the transmission output speed. Estimated 
turbine speed is calculated from engine speed and engine torque. 

Ignition Voltage  

 

2004 Hummer H2 

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

  

This represents the system voltage measured by the PCM at it's ignition feed. 

Last Shift Time  

This parameter is the actual time of the last upshift. This value is only accurate if the shift was adaptable. 

PC Sol. Actual Current  

The Pressure Control Solenoid Actual Current parameter is the actual current of the pressure control 
solenoid circuit at the control module. Zero amp, no current flow, indicates actual higher line pressure. 
Actual lower line pressure is indicated by 1.1 amps, high current flow. 

PC Solenoid Duty Cycle  

This parameter is the commanded state of the pressure control solenoid expressed as a percent of 
energized ON time. Zero percent indicates zero ON time, non-energized, or no current flow. 
Approximately 60% at idle indicates maximum ON time, energized, or high current flow. 

PC Sol. Ref. Current  

The Pressure Control Solenoid Reference Current parameter is the commanded current of the pressure 
control solenoid circuit. Zero amp, no current flow, indicates commanded higher line pressure. 
Commanded lower line pressure is indicated by 1.1 amps, high current flow. 

Power Take-Off  

Displays Yes or No. This parameter indicates when the power Take-Off (PTO) is engaged. PTO mode 
disables all transmission diagnostics. 

Speed Ratio  

This parameter indicates engine speed divided by transmission output speed. This value is used to 
estimate transmission gear ratio. 

TCC Brake Switch  

The Torque Converter Clutch Brake Switch parameter displays Open or Closed. This parameter indicates 
the state of the brake switch circuit input. Open indicates a zero voltage input, brake switch open, brake 
pedal applied. Closed indicates a B+ voltage input, brake switch closed, brake pedal released. 

TCC Duty Cycle  

This parameter is the commanded percentage of ON time of the TCC PWM solenoid. Approximately 
90% represents an ON, energized, commanded state. Zero percent represents an OFF, non-energized, 
commanded state. This commanded state is applied at a vehicle speed between approximately 0-16 km/h 
(0-10 mph). 

 

2004 Hummer H2 

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

  

TCC Duty Cycle Open/Short to GND  

Displays Yes or No. This parameter indicates whether an open or a short to ground exists in the TCC 
PWM solenoid valve feedback signal to the PCM. This parameter is valid only when the TCC PWM 
solenoid is commanded OFF, duty cycle is 0%. 

TCC Duty Cycle Short to Volts  

Displays Yes or No. This parameter indicates whether a short to voltage exists in the TCC PWM solenoid 
valve feedback signal to the PCM. This parameter is valid only when the TCC PWM solenoid is 
commanded ON, duty cycle is at maximum. 

TCC Enable  

Displays On or Off. This parameter is the commanded state of the TCC solenoid. On indicates a 
commanded energized state, current is flowing through the solenoid. Off indicates a commanded non-
energized state, current is not flowing through the solenoid. This commanded state occurs at various 
vehicle speeds between applications. 

TCC Enable Open/Short to GND  

Displays Yes or No. This parameter indicates whether an open or a short to ground exists in the TCC 
solenoid valve feedback signal to the PCM. This parameter is valid only when the TCC solenoid is 
commanded OFF. 

TCC Enable Short to Volts  

Displays Yes or No. This parameter indicates whether a short to voltage exists in the TCC solenoid valve 
feedback signal to the PCM. This parameter is valid only when the TCC solenoid is commanded ON. 

TCC Slip Speed  

This parameter is the difference between transmission output speed and engine speed. A negative value 
indicates that the engine speed is less than the output speed, deceleration. A positive value indicates that 
the engine speed is greater than the output speed, acceleration. A value of zero indicates that the engine 
speed is equal to the output speed, TCC applied. 

TFP Sw.  

The Transmission Fluid Pressure Switch parameter displays Park/Neutral, Reverse, Drive4, Drive3, 
Drive2, Drive1 or Invalid. This parameter is the decoded status of the three A/B/C inputs from the 
automatic transmission fluid pressure manual valve position switch. Invalid is displayed when the PCM 
does not recognize a valid combination of inputs. 

TFP Sw. A/B/C  

Displays HI/LOW, HI/LOW. This parameter indicates the status of the three inputs from the Automatic 

 

2004 Hummer H2 

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

  

Transmission Fluid Pressure Manual Valve Position Switch Assembly to the PCM. LOW represents a 
zero voltage signal. HI represents an ignition voltage signal. 

TFT Sensor  

The Transmission Fluid Temperature Sensor parameter displays a voltage related to the transmission fluid 
temperature. When the transmission fluid is cold, the sensor resistance is high and the PCM will sense 
high signal voltage. As the transmission fluid temperature warms to a normal operating temperature, the 
sensor resistance becomes less and the voltage decreases. 

Torque Converter Efficiency - Ratio  

Displays a ratio of .00:1 to 2:1. The ratio is calculated by multiplying the speed ratio by a value related to 
the "K factor" of the torque converter. The "K factor" is the looseness or tightness of the torque converter 
for a given torque. The nearer the torque converter is to full coupling, i.e. 1:1, the closer the torque 
converter efficiency number will be to 1. 

Tow/Haul Mode  

Displays Active or Inactive. This parameter indicates when the transmission is operating in a towing or 
hauling mode. In tow/haul mode, the PCM commands a different shift pattern that increases performance 
when towing or hauling. Shift quality and TCC scheduling are also affected during tow/haul mode 
operation. 

TP Angle  

The Throttle Position Angle is computed by the PCM from the TP Sensor voltage. The TP angle should 
read 0% at idle and 100% at Wide Open Throttle (WOT). 

TP Indicated Angle  

This parameter indicates the amount of throttle opening. 

TP Sensor  

The Throttle Position Sensor is used by the PCM to determine the amount of throttle demanded by the 
driver. Voltage is below 1 volt at idle and above 4 volts at Wide Open Throttle (WOT). 

TR Sw.  

The Transmission Range Switch parameter displays Park/Neutral, Reverse, Drive4, Drive3, Drive2, 
Drive1 or Invalid. This parameter is the decoded status of the four A/B/C/P inputs from the transmission 
range switch. Invalid is displayed when the PCM does not recognize a valid combination of inputs. 

TR Sw. A/B/C/P  

Displays HI/LOW, HI/LOW. This parameter indicates the status of the four inputs from the transmission 

 

2004 Hummer H2 

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