mode master and is the main message handler
z
The DDM 10A fuse - Located in the I/P fuse block and is hot at all times
z
The PDM 10A fuse - Located in the I/P fuse block and is hot at all times
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The memory switch, if equipped with memory mirrors - Supplied power by the DDM and provides a
voltage signal to the DDM upon a switch activation
z
The horizontal and vertical position sensors, if equipped with memory mirrors - Supplied a 5 volt and low
reference by the DDM/PDM and provide a variable voltage signal to the DDM/PDM that is proportional
to mirror position
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The park neutral position switch, if equipped with memory mirrors - Provides transmission gear selection
information to the PCM and is used for memory recall and mirror tilt in reverse functions
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The powertrain control module, if equipped with memory mirrors - Class 2 module that requires
programming when replaced and provides Class 2 message indicating transmission gear selection
z
The driver Information Center (DIC), if equipped with memory mirrors - Part of the instrument cluster
which is a Class 2 module that requires programming when replaced and is used to personalize the
memory recall and mirror tilt in reverse functions
z
Fold motor in each of the outside mirrors, if equipped with power fold mirrors - Provides extend and
retract movements of the mirror and is serviced as a complete mirror assembly
Each of the outside power mirrors contains 2 reversible motors to provide horizontal and vertical movement of
the mirror glass. The vertical motor operates the up and down directions and the horizontal motor operates the
left and right directions. If equipped with power folding mirrors, each outside power mirror will contain a
reversible fold motor to operate the extend and retract functions. Each of the mirror motors are circuit breaker
protected.
Power Mirror System Controls
The power mirror switch incorporates a 3 position mirror select switch and a 4 position mirror direction switch.
The mirror select switch allows the operator to select the mirror to be moved by selecting the L position for the
left power mirror, selecting the R position for the right power mirror or the center which is the neutral/fold
position. The mirror direction switch is a 4 position switch that allows the operator to move the selected mirror
up, down, left or right. The mirror direction switch also functions as the folding mirror switch. When the
selector switch is in the neutral/fold position, activate the mirror direction switch to the left to extend the
mirrors and right to retract the mirrors.
Power Mirror System Operation
The power mirror switch is integrated into the DDM. The left and right mirror positions of the select switch and
4 positions of the direction switch, when active, will provide a signal to the DDM. If the selector switch is
placed in the L position and the up switch is depressed, 2 signals will be supplied to the DDM. The DDM upon
receipt of these signals will provide battery voltage to the mirror motor left/up control circuit and ground to the
mirror motor down control circuit and the mirror will move up. The remainder of the driver mirror functions
operate in the same manner as described above except the DDM will supply battery voltage and ground to the
appropriate control circuits for the direction selected. If the passenger mirror is selected and a direction switch is
activated, the DDM sends a class 2 message to the PDM indicating that the passenger mirror was selected and
the direction to be commanded. The PDM will then supply battery voltage and ground to the appropriate control
2004 Hummer H2
2004 ACCESSORIES & EQUIPMENT Doors - Hummer H2