Lebaron Coupe L4-135 2.2L SOHC Turbo VIN A FI (1989)
Variable Damping Control Module: Description and Operation
Fig. 2 Variable Dampening Suspension Wiring Circuit
The VDCM is used to monitor and control the VDS system. The VDCM has one 25-Way connector and is attached to a bracket in the lefthand side of
the trunk. The diagnostic connector is also located in the trunk. The VDCM uses a 6-way connector to access DRB II diagnostics. The VDS system,
including the VDCM, is grounded at the left rear quarter panel inside the trunk (circuit Z02A).
VDCM INPUTS
The VDCM receives power from the battery through the ignition switch (circuit F20A).
The VDCM receives information from two selector switches located on the center console. The position of these switches tell the module which
damping position has been selected.
The VDCM also monitors and receives information from eight Position Feedback Switches (PFS). Two PFS are located in each shock/strut. These
switches indicate the present damping position of the shocks/struts.
VDCM OUTPUTS
The VDCM controls four small electric motors. One motor is located in each shock/strut. These motors vary the sizes of the fluid orifices in the
shock/struts to achieve the different damping positions.
The VDCM also controls three LEDs on the switch bezel in the center console which indicate the present setting of the VDS system. The VDCM dims
the LEDs when the headlamps are On and brightens the LEDs when the headlamps are Off. The VDCM uses the park lamp dim input (pin 14) to
determine is the headlamps are On or Off. The LEDs are also used to inform if a system fault occurs.
VDCM RESET
The VDCM has a volatile memory and will reset whenever the ignition is turned On. When the VDCM is reset it will: Clear the VDCM memory of
any faults; Read selector switch inputs; Attempt to drive the motors in the shocks/struts to the selected damping position if they are not already in the
selected position.
The VDCM can be reset two additional ways. First, by grounding the diagnostic input pin (pin 13) for three seconds, then ungrounding the pin and
