Hummer H3. Manual — part 1633

Electronic Park Lock (EPL)/Ignition Lock Cylinder Control Actuator

If the vehicle is equipped with automatic transmission and a floor mounted console gear
shift, it has an ignition lock cylinder control actuator system in the steering column. The
ignition lock cylinder control actuator purpose is to prevent the ignition key from being
turned to the OFF position when the transmission is in any position other than PARK and
the vehicle may still be moving. The column ignition lock system consists of an ignition lock
cylinder control actuator and a park position switch that is located in the automatic
transmission shift lock control switch. The ignition lock cylinder control actuator contains a
pin that is spring loaded to mechanically prevent the ignition key cylinder from being turned
to the lock position when the vehicle transmission is not in the PARK position. If vehicle
power is lost, and/or the transmission is not in the PARK position the operator will not be
able to turn the ignition key to the lock position and will not be able to remove the ignition
key from the column.

Linear Shift Assembly

If the vehicle is equipped with a column mounted gear shift, it has a linear shift assembly on
the steering column. The linear shift assembly has a cable that runs from the linear shift
assembly to the ignition lock cylinder case. The purpose of this cable is to prevent the
ignition key from being turned to the OFF position when the transmission is in gear and the
vehicle may still be moving. The linear shift assembly cable contains a pin that is spring
loaded to mechanically prevent the ignition key cylinder from being turned to the lock
position when the vehicle transmission is not in the PARK position. If vehicle power is lost,
and/or the transmission is not in the PARK position the operator will not be able to turn the
ignition key to the lock position and will not be able to remove the ignition key from the
column.

SIR Coil and Module

For additional information on the operation of the SIR coil and module, refer to SIR
System Description and Operation .

Automatic Transmission Shift Lock Actuator

The automatic transmission shift lock control system is a safety device that prevents an
inadvertent shift out of PARK when the engine is running. The driver must press the brake
pedal before moving the shift lever out of the PARK position. The system consists of the
following components: the automatic transmission shift lock control solenoid, the automatic
transmission shift lock control switch, the body control module (BCM), the powertrain
control module (PCM)/engine control module (ECM). With the ignition in the ON position,

2007 Hummer H3

2007 STEERING Steering Wheel and Column - H3

voltage is supplied to automatic transmission shift lock control switch. Voltage flows
through the normally closed contacts of the automatic transmission shift lock control switch
to the automatic transmission shift lock control solenoid. When the BCM receives a class 2
message from the PCM/ECM indicating the transmission is in the park position the BCM
then grounds the automatic transmission shift lock solenoid control circuit. This energizes
the automatic transmission shift lock control solenoid causing the transmission shift lever to
be physically locked in the PARK position. When the brake pedal is pressed the contacts in
the automatic transmission shift lock control switch open, de-energizing the automatic
transmission shift lock control solenoid. This allows the shift lever to be move out of the
PARK position.

Steering Wheel Angle Sensor or Steering Wheel Position Sensor

The steering wheel position sensor is located somewhere along the steering shaft assembly.
The sensor measures the position of the steering wheel and the speed at which it is rotated.
A signal representing this measurement is provided to the vehicle stability enhancement
system (VSES) module. The VSES module uses this signal, along with several others
representing different vehicle conditions, to monitor the driving behavior of the vehicle and
ensure that it stays in control. If the VSES module determines that the vehicle is out of
control it provides signals to the powertrain control module (PCM) and the ABS module.
These output signals are used to modulate the transmission torque and brake pressure of each
of the vehicles wheels in order to regain control of the vehicle.

SPECIAL TOOLS AND EQUIPMENT

SPECIAL TOOLS

Special Tools

Illustration

Tool Number/Description

J-21854-A

Pivot Pin Remover

2007 Hummer H3

2007 STEERING Steering Wheel and Column - H3

J-42640

Steering Column Anti-Rotation Pin

2007 Hummer H3

2007 STEERING Steering Wheel and Column - H3

2007 ACCESSORIES & EQUIPMENT

Sunroof - H3

SPECIFICATIONS

FASTENER TIGHTENING SPECIFICATIONS

Fastener Tightening Specifications

SCHEMATIC AND ROUTING DIAGRAMS

SUNROOF SCHEMATICS

Application

Specification

Metric

English

Sunroof Sunshade Handle Screws

2 N.m

18 lb in

Sunroof Air Deflector

3 N.m

27 lb in

Sunroof Drain Weeper

2 N.m

18 lb in

Sunroof Module Retaining Bolts

9 N.m

80 lb in

Sunroof Module Retaining Nuts

9 N.m

80 lb in

Sunroof Motor Bolts

6 N.m

53 lb in

Sunroof Window

4 N.m

35 lb in

Sunshade Panel Rubber Stoppers

3 N.m

27 lb in

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Sunroof - H3

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Sunroof - H3