Hummer H2. Manual - part 2380

Fig. 491: Torque Converter Clutch Solenoid Valve 
Courtesy of GENERAL MOTORS CORP. 

The torque converter clutch (TCC) solenoid valve is a normally-open exhaust valve that is used to control 
torque converter clutch apply and release. When grounded (energized) by the powertrain control module 
(PCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes converter signal oil 
pressure to increase and move the TCC solenoid valve into the apply position.

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E (Introduction) - Hummer H2

  

Torque Converter Clutch Pulse Width Modulation Solenoid Valve

Fig. 492: Torque Converter Clutch Pulse Width Modulation Solenoid Valve (M30/M32) 
Courtesy of GENERAL MOTORS CORP. 

The torque converter clutch pulse width modulation solenoid valve controls the fluid acting on the converter 
clutch valve. The converter clutch valve controls the torque converter clutch (TCC) apply and release. This 
solenoid is attached to the control valve body assembly within the transmission. The TCC PWM solenoid valve 
provides a smooth engagement of the torque converter clutch by operating during a duty cycle percent of ON 
time. 

Transmission Fluid Pressure (TFP) Manual Valve Position Switch 

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E (Introduction) - Hummer H2

  

Fig. 493: Transmission Fluid Pressure (TFP) Manual Valve Position Switch (M33 Only) 
Courtesy of GENERAL MOTORS CORP. 

The transmission fluid pressure (TFP) manual valve position switch consists of five pressure switches (two 
normally-closed and three normally-open) on the control valve body that sense whether fluid pressure is present 
in five different valve body passages. The combination of switches that are open and closed is used by the PCM 
in order to determine the actual manual valve position. The TFP manual valve position switch, however, cannot 
distinguish between PARK and NEUTRAL because the monitored valve body pressures are identical in both 
cases. 

The switches are wired to provide three signal lines that are monitored by the PCM. These signals are used to 
help control line pressure, torque converter clutch apply and shift solenoid valve operation. Voltage at each of 
the signal lines is either zero or twelve volts. 

In order to monitor the TFP manual valve position switch operation, the PCM compares the actual voltage 
combination of the switches to a TFP combination table stored in its memory. 

The TFP manual valve position switch signal voltage can be measured from each pin-to-ground and compared 
to the combination table. On the automatic transmission (AT) wiring harness assembly, pin N is signal A, pin R 
is signal B, and pin P is signal C. With the AT wiring harness assembly connected and the engine running, a 
voltage measurement of these three lines will indicate a high reading (near 12 volts) when a circuit is open, and 
a low reading (zero volts) when the circuit is switched to ground. 

The transmission fluid temperature (TFT) sensor is part of the TFP manual valve position switch assembly.

IMPORTANT: Seven valid combinations and two invalid combinations are available from the 

TFP manual valve position switch. Refer to the Transmission Fluid Pressure 
(TFP) Manual Valve Position Switch Logic table for valid/invalid combinations 
for range signal circuits A, B and C.

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E (Introduction) - Hummer H2

  

Vehicle Speed Sensor Assembly 

Fig. 494: View Of Vehicle Speed Sensor Assembly 
Courtesy of GENERAL MOTORS CORP. 

The vehicle speed sensor (VSS) assembly provides vehicle speed information to the PCM. The VSS assembly is 
a permanent magnet (PM) generator. The PM generator produces a pulsing AC voltage as rotor teeth on the 
transmission output shaft pass through the sensor's magnetic field. The AC voltage level and the number of 
pulses increase as the speed of the vehicle increases. Output voltage varies with speed from a minimum of 0.5 

 

2004 Hummer H2 

2004 TRANSMISSION Automatic Transmission - 4L60-E/4L65-E (Introduction) - Hummer H2