Chrysler 1998 Voyager Service Manual page 532

8R - 4 POWER SEATS
DESCRIPTION AND OPERATION (Continued)
two positions of seat and recliner, and the side view
mirrors as chosen by the driver.
The inputs from these switches to the memory
seat/mirror module is a ground level signal.
(1) Adjust the seat, recliner and side view mirrors
to the desired position.
(2) Press momentarily and release memory switch S.
(3) Press momentarily and release memory switch
1 or 2. Do NOT press any switches for 10 seconds.
(4) To program the second driver's position, follow
the above sequence.
(5) To recall either of the programmed positions
momentarily press and release either memory selec-
tor switch 1 or 2.
DEFINITION OF: MOMENTARILY AND
RELEASE
The memory seat/mirror module has switch input
timing requirements of a minimum press momen-
tarily time of 250 milliseconds followed by a maxi-
mum hold time of 5 seconds, followed by a maximum
release time between steps of 5 seconds that must be
met for proper operation of the system.
SEAT AND RECLINER SWITCHES
The seat and recliner switch assembly is mounted
outboard on the seat side-shield. Press and hold the
desired seat or recliner switch to effect movement.
The Memory Seat/Mirror Module (MSM Module) will
drive a maximum of 2 motors at a time in a given
direction. If conflicting directions are requested, the
priority for response will be as follows:
• Seat Track Rearward
• Seat Front Down
• Seat Rear Down
• Recliner Rearward
• Seat Track Forward
• Seat Front Up
• Seat Rear Up
• Recliner Forward
The inputs from these switches to the MSM Mod-
ule is a current limited battery source fed by the
MSM Module. This protects the MSM Module printed
circuit board traces from acting as fuses. All of these
switch contact inputs to the module are normally
closed to ground, except when actuated.
POSITION SENSING SEAT AND RECLINER
POTENTIOMETERS
A potentiometer is mounted to each seat track and
recliner motor end-bell to provide a sense voltage to
the Memory Seat/Mirror Module that will indicate to
the module where the seat track or recliner is posi-
tioned.
This sense voltage is derived from a 5 volt source
provided by the module to the potentiometer. The
sense voltage is input into the module and stored by
the Memory Seat/Mirror Module.
DIAGNOSIS AND TESTING
MEMORY SELECTOR SWITCHES
To test the memory selector switch:
(1) Remove the memory selector switch. Refer to
removal procedure.
(2) Using an ohmmeter check continuity reading
between switch pins. Refer to (Fig. 1) for proper Pin
numbers.
Fig. 1 Memory Selector Switch Continuity
SIDE VIEW MIRROR SWITCH STUCK
The mirror switches in the instrument panel have
normally open contacts when in their inactive state.
The left/right rocker switch has a center-off detent. If
this switch is actuated to either side, it then becomes
connected to the P73/P70, circuits which are the mir-
ror motor common connections. No faults will result
from this action by itself. If one of the other switch
contacts from the round portion of the switch
becomes accidentally closed, It can cause problems
such as both mirrors operating at the same
time in the vertical or horizontal modes.
• Turn ignition switch ON: If two mirror switch
contacts, from the round portion, are stuck in the
closed position, and the left/right portion is actuated
to either side, a mirror motor will become actuated.
This will drive the motor to its stop, where it will
keep ratcheting until a switch contact is released or
the ignition is turned to OFF. Replace the mirror
switch assembly to correct this condition.
• With the ignition switch in the ON or the OFF
position: If only one mirror switch contact is stuck in
the closed position, the mirror motor will not become
actuated. During an ignition switch recall of a driv-
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