long as the front Wash switch is held closed, and to
de-energize when the front Wash switch is released.
When the control stalk of the right (wiper) multi-
function switch is moved to the momentary front
Wash position while the control knob is in one of the
Delay interval or Auto sensitivity positions, the front
washer pump/motor operation is the same. However,
the BCM sends a bus message to the IPM to energizes
the wiper on/off relay to override the selected delay
interval or auto sensitivity level and operate the front
wiper motor in a continuous low speed mode for as
long as the front Wash switch is held closed, then de-
energizes the relay and reverts to the selected delay
mode interval or auto sensitivity level several wipe
cycles after the front Wash switch is released. The
BCM detects the front Wash switch state through a
hard wired washer pump motor switch output circuit
input from the right multi-function switch.
WIPE-AFTER-WASH MODE
When the control stalk of the right (wiper) multi-
function switch is moved to the momentary front
Wash position while the control knob is in the Off
position, the BCM detects that switch state through
a hard wired washer pump motor switch output cir-
cuit input from the right multi-function switch. The
BCM responds to this input by sending a PCI data
bus message to the IPM to energize the washer
pump as long as the Wash switch is held closed, then
de-energizes the washer pump several wipe cycles
after the front Wash switch is released. The BCM
monitors the changing state of the wiper motor park
switch through a hard wired front wiper park switch
sense circuit input. This input allows the BCM to
count the number of wipe cycles that occur after the
front Wash switch state changes to open, and to
determine the proper interval at which to sends a
PCI data bus message to the IPM to de-energize the
washer pump to complete the wipe-after-wash mode
cycle.
REAR WIPER/WASHER SYSTEM
The vehicle operator initiates all rear wiper and
washer system functions with the control stalk of the
right multi-function switch that extends from the
right side of the steering column, just below the
steering wheel. Rotating the control sleeve on the
control stalk to a detent position selects the rear
wiper system operating mode. Moving the switch con-
trol stalk forward actuates the momentary rear
washer system switch. The right multi-function
switch provides hard wired outputs to the rear wiper
motor and the rear washer pump/motor for all rear
wiper and washer system functions.
The rear wiper and washer system will only oper-
ate when the ignition switch is in the Accessory or
On positions. When the ignition switch is in the
Accessory or On positions, battery current from a
fuse in the IPM is provided to the right multi-func-
tion switch through a fused ignition switch output
(run-acc) circuit. The internal circuitry of the right
(wiper) control stalk of the right multi-function
switch then provides battery current signals through
a rear wiper motor control circuit and a rear wiper
motor delay control circuit to the rear wiper motor.
The multi-function switch circuitry also uses this bat-
tery current input to directly control the operation of
the rear washer pump/motor unit.
When diagnosing the rear wiper/washer system,
use of a DRBIII
t scan tool and refer to the appropri-
ate Body Diagnostic Procedures manual.
REAR WIPER/WASHER OPERATING MODES
CONTINUOUS WIPE MODE
When the On position of the control sleeve on the
right (wiper) multi-function switch control stalk is
selected, the multi-function switch circuitry directs a
battery current signal to the rear wiper motor
through the rear wiper motor control circuit, causing
the rear wiper to cycle continuously at a fixed speed.
INTERMITTENT WIPE MODE
When the Delay position of the control sleeve on
the right (wiper) multi-function switch control stalk
is selected, the multi-function switch circuitry directs
a battery current signal to the rear wiper motor
through the rear wiper motor delay control circuit,
causing the rear wiper to cycle intermittently at a
fixed delay interval.
WASH MODE
When the control stalk of the right (wiper) multi-
function switch is moved to the momentary Wash
position, the multi-function switch circuitry directs
battery current to the rear washer pump/motor
through the rear washer pump motor control circuit,
and battery current signals are also provided to the
rear wiper motor on both the rear wiper motor con-
trol circuit and the rear wiper motor delay control
circuit. This will cause the rear washer pump/motor
to be energized and the rear wiper to cycle continu-
ously at a fixed speed for as long as the rear Wash
switch is held closed.
WIPE-AFTER-WASH MODE
When the control stalk of the right (wiper) multi-
function switch is released from the momentary
Wash position, the rear washer pump/motor is de-en-
ergized, but the circuitry within the rear wiper motor
will provide several additional wipe cycles to com-
plete the wipe-after-wash mode cycle.
CS
WIPERS/WASHERS
8R - 5
WIPERS/WASHERS (Continued)