REAR WINDOW DEFOGGER
RELAY
DESCRIPTION
The left and right rear window defogger (EBL)
relays
are
International
Standards
Organization
(ISO)-type relays (Fig. 3). Relays conforming to the
ISO specifications have common physical dimensions,
current capacities, terminal functions and patterns.
The EBL relays are electromechanical devices that
switch battery current through fuse 10 (30 amp)
located in the fuse/relay block under the driver seat
to
the
rear
window
defogger
grids
and
when
equipped, switches battery current to the outside
mirror heating grids. The EBL relays are energized
when the relay coils are provided battery current by
the rear window defogger module.
The EBL relays are located in the fuse/relay block
under the driver seat. Refer to the fuse and relay
map located on the inner surface of the fuse/relay
block cover for the left and right rear window defog-
ger (EBL) relay locations.
The black, molded plastic case is the most visible
component of the two rear window defogger (EBL)
relays. Five male spade-type terminals extend from
the bottom of the base to connect each relay to the
vehicle electrical system, and the ISO designation for
each terminal is molded into the base adjacent to
each terminal.
OPERATION
The left and right rear window defogger (EBL)
relays are electromechanical switches that uses a low
current input from the rear window defogger module
to control the high current output to the rear window
defogger grids. The movable common feed contact
point is held against the fixed normally closed con-
tact point by spring pressure. When the relay coil is
energized, an electromagnetic field is produced by the
coil windings. This electromagnetic field draws the
movable relay contact point away from the fixed nor-
mally closed contact point, and holds it against the
fixed normally open contact point. When the relay
coil is de-energized, spring pressure returns the mov-
able contact point back against the fixed normally
closed contact point. The resistor or diode is con-
nected in parallel with the relay coil in the relay, and
helps to dissipate voltage spikes and electromagnetic
interference that can be generated as the electromag-
netic field of the relay coil collapses.
The EBL relay terminals are connected to the vehi-
cle electrical system through receptacles in the fuse/
relay block. The inputs and outputs of the EBL
relays include:
•
The common feed terminal (30) receives a bat-
tery current input from fuse 10 (30 amp) in the fuse/
relay block through a fused B(+) circuit at all times.
Fig. 2 Grid Line Test
1 - VOLTMETER
2 - VOLTAGE FEED (A)
3 - FEED WIRE
4 - MID-POINT (C)
5 - HEATED WINDOW GRID
6 - GROUND WIRE
7 - GROUND (B)
Fig. 3 Rear Window Defogger (EBL) Relays
1 - REAR WINDOW DEFOGGER (EBL) RELAY (2)
2 - TERMINAL PATTERN
VA
HEATED GLASS
8G - 3
