Position Feedback Switches (PFS)

Fig. 5 PFS System Voltages:

Fig. 6 Control Module Connector Identification:

There are eight Position Feedback Switches (PFS), two in each shock and strut, one Soft, and one Firm. A PFS monitors the orifices in the shock or strut, and tell the VDCM which damping position the shock or strut is presently in.

PFS INPUT CHANGES

There are four possible positions that a PFS could be in. Soft, Norm, Firm or Illegal. The PFS will be in the Illegal position if there is a system malfunction. If the motor in the shock/strut drifts, causing the PFS input to change and there has been no over current fault (short to ground or internal motor short) since the last Reset, the module will drive the motor(s) in question until the PFS input is correct. The PFS input is correct when the PFS tells the module that the shock or strut is in the selected damping position. If two seconds pass and PFS input is still incorrect, the module will enter the Fault mode.
Refer to voltages of the PFS circuits when the shocks/struts are in the various positions. The pin numbers refer to the pins at the VDCM 25-Way connector.