The heated sea t rela y cannot be repa ired or
adju st ed and, if faulty or dama ged, it must be
repla ced.
OPERATION
The ISO relay consists of an electromagnetic coil, a
resistor or diode, an d three (t wo fixed and one mov-
able) electrical conta cts. The movable (common feed)
rela y contact is h eld again st one of the fixed contacts
(normally closed) by spring pressur e. When t he elec-
tromagnetic coil is en ergized, it draws the movable
contact away from the n orma lly closed fixed contact,
and holds it a gainst the ot her (n ormally open ) fixed
contact. When the electromagn etic coil is de-ener-
gized, spring pr essu re ret urns t he movable contact t o
the n ormally closed position. Th e resist or or diode is
connect ed in par allel with t he electrom agn etic coil in
the relay, a nd h elps to dissipate volt age spikes that
are pr odu ced when th e coil is de-en ergized.
DIAGNOSIS AND TESTING - HEATED SEAT
RELA Y
The heated sea t relay is locat ed in the Fuse Block,
under th e driver s seat. Refer to Wi ri n g for the loca-
tion of complet e hea ted seat system wirin g dia gra ms.
(1) Remove the h eated seat rela y from t he fuse
block.
(2) A relay in the de-en ergized position should
have continuity between term inals 87A an d 30, an d
no continuity between term ina ls 87 and 30. If OK, go
to Step 3. If not OK, repla ce the fa ult y relay.
(3) Resista nce between termina ls 85 and 86 (elec-
tromagnet) shou ld be 75 ± 5 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a bat tery to t erminals 85 and 86.
There should now be cont inu ity between terminals
30 and 87, and no cont inuity between t erminals 87A
and 30. If OK, check th e r elay su pply circu its. If not
OK, replace t he faulty relay.
REMOVAL
(1) Disconn ect and isolate the battery nega tive
cable.
(2) The h eated seat r elay is located in the fuse
block, u nder th e drivers seat. Refer to wir ing for
detailed location.
(3) Grasp the h eated seat relay firmly and pu ll it
st raight out fr om the fu se block. A slight rockin g
motion will aid in remova l.
INSTALLATION
(1) Grasp the hea ted seat relay firmly and pu sh it
st raight in the fuse block.
(2) Reconnect t he battery negative cable.
HEATED SEAT SENSOR
DESCRIPTION
The h eated sea t temper atur e sensor is a Nega tive
Temperatur e Coefficien t (NTC) thermistor. One tem-
perat ure sensor is used for each seat . The sensor is
locat ed in th e seat cushion hea ting elemen t for all
models.
The heated sea t sensor ca nnot be adjusted or
repaired and if it is fou nd t o be faulty, th e com plete
heat ed seat element must be replaced.
DIAGNOSIS AND TESTING - HEATED SEAT
SENSOR
For complete circuit diagram s, refer to Wi r i n g .
NOTE: Any resistance values (ohms !) given in the
following text are supplied using the automatic
range generated by a FLUKE" automotive meter. If
another type of measuring device is used the val-
ues generated may not be the same as the results
shown here, or may have to be converted to the
range used here.
(1) Backprobe the hea ted sea t relay wire harness
connect or, do not disconnect . Using an voltm eter,
check the volt age of the seat temperatur e sen sor
input ca vity of th e heat ed seat relay wir e har ness
connect or. The sea t sensor input voltage should be
between 1.7 volts and 3.0 volts with the system ON.
If OK, sensor is OK at th is time. If not OK, r eplace
the fa ulty seat cu sh ion heating elemen t and sensor
assembly.
PASSEN GER H EAT ED SEAT
SWI T CH
DESCRIPTION
The hea ted seat switches are loca ted on the instr u-
ment pa nel, in th e accessory switch bezel. The t wo,
momen tary rocker type switch es pr ovide a signal to
the Heated Sea t Rela y t hrough separate ha rd wir ed
circuits. Each swit ch con tains two ligh t emit ting
diodes (LED), one for ea ch High and Low setting t o
let th e occupan t kn ow that th e seat heater system is
on.
The hea ted sea t switches an d their LED’s ca nnot
be repa ired. If either switch is faulty or dama ged th e
entire switch mu st be replaced.
OPERATION
There are three modes that can be selected with
each of the heated seat swit ches: Off, Low, and High.
When the top of th e switch rocker is depr essed, t he
low mode is select ed and the low mode LE D in dicator
illuminates. Depressing the top of th e switch rocker a
VA HEA TED SEA TS 8G - 13
To Next Page
Loading...
