Pontiac Fiero 1988 Service Manual page 1226

WINDSHIELD WIPER SYSTEMS 8E2-1
SECTION 8E2
PM POSITIVE PARK PULSE WIPER WASHER
NON-DEPRESSED PARK SYSTEM
CONTENTS
General Description
Permanent Magnet Pulse Windshield
Wiper Motor 8E2-1
Wiper Motor 8E2-1
Fluidic Washer Nozzle 8E2-1
Wiper Washer Operation ...............................
8E2-3
Low and High Speed Circuits .................... 8E2-3
Shutting the Wiper Off ............................... 8E2-3
Washer Pump Operation ............................ 8E2-3
Diagnosis 8E2-3
Windshield Wiper System Tester ...............
8E2-3
Diagnostic Procedure 8E2-3
Wiper Motor ............................................... 8E2-5
Washer Pump .............................................
8E2-5
Wiper/Washer Multi-Function Lever
Test
8E2-5
On-Car/Off-Car Service 8E2-6
Wiper Arm (R & R)
8E2-6
Wiper Blade (R & R) ................................. 8E2-7
Wiper Blade Element (R & R) ..................
8E2-7
Wiper Transmission Assembly (R & R) ....
8E2-7
Wiper Motor
8E2-7
Circuit Board Replacement
8E2-11
Crank Arm Replacement
8E2-11
GENERAL DESCRIPTION
PERMANENT MAGNET PULSE WINDSHIELD
WIPER MOTOR
The two-speed wiper non-depressed park system
is a permanent magnet (PM) positive park wiper with
a dynamic brake and a separate washer pump
assembly.
The pulse windshield wiper and washer system
consists of a permanent magnet positive park pulse
wiper, a washer pump mounted in the washer bottle
and a turn signal type wiper/washer switch.
The pulse and demand wash functions are
controlled by a plug-in printed circuit board enclosed
in the wiper's housing cover.
WIPER MOTOR
Internal parts of the wiper motor assembly, field
magnet, armature, drive gear, park switch actuator and
brush holding assembly are enclosed in an aluminum
die-cast housing with a plastic cover. The housing and
cover are attached to each other by seven rivets. A
radio frequency interference suppressor is located in
the terminal connector on the wiper motor. A strap
attached to one of the motor bolt hole grommets
provides a ground for the suppressor. An automatic
reset type circuit breaker located on the motor brush
holder assembly protects the motor. A fuse in the fuse
block protects the vehicle wiring.
Referring to Fig. 3, note that there are four
terminals which are lettered for illustrative purposes.
The function of each terminal is covered in the
explanation that follows.
Use care when disconnecting the lock-type
connectors that attach vehicle wiring to the
wiper.
As shown in Fig. 3, the wiper motor has three
brushes: common, low speed and high speed. When the
ignition switch is ON, 12V plus circuit is applied to
both the low and high speed fixed contacts in the
3 2 4 9
Fig. 1 Permanent Magnet Pulse Windshield Wiper Motor
multi-function lever. The low and high speed brushes
are connected to the multi-function lever through
terminals C and D. The armature is grounded through
the common brush via the ground strap.
FLUIDIC WASHER NOZZLE
(Fig.
2)
The system consists of a fluid container, pump,
fluidic hose and nozzle.
The fluidic washer system is controlled by a small
plastic element designed into the washer nozzle. As
water is forced through this insert, the design of the
mechanism creates an oscillating power stream. This
fluidic washer system produces larger, more widely
dispersed droplets, resulting in a more efficient
• cleaning action.
A correctly operating wiper-washer system has a
spray pattern that cleans 75% of the wipe pattern
within ten
wiper cycles.
If the nozzles become plugged, apply air pressure.
If nozzle remains
plugged, the nozzle must be replaced.
If the spray pattern
is too low or too high on the
windshield, wedge-type adjustment shims can be used.