WINDSHIELD WIPING/WASHING
• The GM III controls all of the windshield wiping/washer and headlight washing functions.
• Output control of the wiper motor is
through the windshield wiper double
contact relay. The relay is located in the
engine compartment E-box and is tan in
color.
• The system continues to have four wiping
stages and four interval wiping speeds.
The wiping stage inputs are coded signals
through a two wire link with a combination
of high/low inputs as on previous
systems.
• The Windshield Wiping System can also be supplemented with the Rain Sensor system
as optional equipment. The Rain Sensor detects rain drops on the windshield and
automatically activates the wipers when the stalk switch is in the intermittent position.
Wiper Stalk Switch:
SINGLE: Holding the wiper switch down in the single position provides a ground signal to
activate the slow speed circuit providing wiper operation until the switch is released.
INTERMITTENT: The intermittent wiping time inputs are provided by a potentiometer
mounted in the wiper stalk switch.
• The intermittent
wiping intervals are
dependent on the
road speed.
• As road speed
increases, the
wiping interval
delay is decreased.
SLOW (I) AND FAST (II): The stage I and stage II wiping speeds are also affected by road
speed. The factory encoded settings are the same as previous systems:
• Stage I automatically switches to intermittent when the vehicle is stopped
• Stage II switches to stage I when stopped.
ZKE - 6
WINDSHIELD WIPER
DOUBLE RELAY
ZKE - 8
WINDSHIELD WASHING:
Pulling the Windshield Wiper Switch rearward closes the “wash” contact providing a
switched ground input to the GM. The GM activates the windshield washer pump directly
via a power output final stage transistor.
HEADLIGHT WASHING:
When the headlights are on, the headlight
washer pump is activated with the first
activation of the windshield washer pump.
The GM recognizes headlights on via K bus
signalling.
Within the same “on” cycle (ignition key has
not been switched off), it is only activated
again after five successive windshield washer
cycles.
The GM provides a ground on the headlight
washer relay control circuit providing pump
operation. The relay is located in the e-box.
The X5 uses three separate washer pumps
which are all easily accessible on the 5.3 liter
washer fluid reservoir located in the engine
compartment.
GM III
HEADLIGHT WASHER
RELAY
HEADLIGHT
WASHER
PUMP
WINDSHIELD
WASHER
PUMP
TAILGATE
WASHER
PUMP
