Jeep Cherokee 2000 Service Manual - page 508
of the switch. The resistance reading should be about
32.5 Ohms. If OK, see Heated Seat Relay in the
Diagnosis and Testing section of this group. If not
OK, replace the faulty switch.
HEATED SEAT ELEMENT and SENSOR
The wire harness connectors for the seat cushion
and seat back heating elements are located under the
seat, near the rear edge of the seat cushion frame.
For circuit descriptions and diagrams, refer to 8W -
63 - Power Seat With Heated Seats in Group 8W -
Wiring Diagrams.
SEAT CUSHION
(1) Disconnect and isolate the battery negative
cable. Unplug the 4-way heated seat cushion wire
harness connector.
(2) Check for continuity between the two heated
seat element circuit cavities of the seat cushion cover
half of the heated seat cushion wire harness connec-
tor. There should be continuity. If OK, go to Step 3. If
not OK, replace the faulty seat cushion cover.
(3) Check for continuity between one of the heated
seat element circuit cavities of the seat cushion cover
half of the heated seat cushion wire harness connec-
tor and the seat cushion frame. There should be no
continuity. If OK, see Seat Back in the Diagnosis and
Testing section of this group. If not OK, replace the
faulty seat cushion cover.
SEAT BACK
(1) Disconnect and isolate the battery negative
cable. Unplug the 2-way heated seat back wire har-
ness connector.
(2) Check for continuity between the heated seat
element circuit cavity and the ground circuit cavity of
the seat back cover half of the heated seat back wire
harness connector. There should be continuity. If OK,
go to Step 3. If not OK, replace the faulty seat back
cover.
(3) Check for continuity between the heated seat
element circuit cavity of the seat back cover half of
the heated seat back wire harness connector and the
seat back frame. There should be no continuity. If
OK, see Heated Seat Sensor in the Diagnosis and
Testing section of this group. If not OK, replace the
faulty seat back cover.
HEATED SEAT SENSOR
The wire harness connector for the seat cushion
heating element and sensor are located under the
seat, near the rear edge of the seat cushion frame.
For circuit descriptions and diagrams, refer to 8W -
63 - Power Seat With Heated Seats in Group 8W -
Wiring Diagrams.
(1) Disconnect and isolate the battery negative
cable. Unplug the 4-way heated seat cushion wire
harness connector.
(2) Using
an
ohmmeter,
check
the
resistance
between the heated seat sensor input circuit cavity
and the heated seat sensor feed circuit cavity of the
seat cushion cover half of the heated seat cushion
wire harness connector. The sensor resistance should
be between 1 Kohm and 200 Kohms. If OK, see
Heated Seat Relay in the Diagnosis and Testing sec-
tion of this group. If not OK, replace the faulty seat
cushion cover.
HEATED SEAT RELAY
For circuit descriptions and diagrams, refer to 8W -
63 - Power Seat With Heated Seats in Group 8W -
Wiring Diagrams.
(1) Disconnect and isolate the battery negative
cable. Unplug the 8-way heated seat relay connector.
(2) Check for continuity between the ground cir-
cuit cavity of the 8-way heated seat relay wire har-
ness connector and a good ground. There should be
continuity. If OK, go to Step 3. If not OK, repair the
open circuit as required.
(3) Connect the battery negative cable. Check for
battery voltage at the battery feed circuit cavity (pin
8) of the 8-way heated seat relay wire harness con-
nector. If OK, go to Step 4. If not OK, repair the open
circuit as required.
(4) Turn the ignition switch to the ON position.
Check for battery voltage at the fused ignition switch
output circuit cavity of the 8-way heated seat relay
wire harness connector. If OK, turn the ignition
switch to the OFF position, disconnect and isolate
the battery negative cable, and go to Step 5. If not
OK, repair the open circuit as required.
(5) Unplug the 14-way seat heat interface module
(SHIM) connector. Check for continuity between the
two switched battery feed cavities of the 14-way
SHIM wire harness connector and the switched bat-
tery feed cavity of the 8-way heated seat relay wire
harness connector. If OK, reconnect the heated seat
relay wire harness connector, and go to Step 6. If not
OK, repair the open circuit as required.
(6) Connect the battery negative cable. Turn the
ignition switch to the ON position. Check for battery
voltage at the switched battery feed cavities of the
14-way SHIM wire harness connector. If OK, turn
the ignition switch to the OFF position, disconnect
and isolate the battery negative cable, and see Seat
Heat Interface Module in the diagnosis and testing
section of this group. If not OK, replace the heated
seat relay.
XJ
ELECTRICALLY HEATED SYSTEMS
8N - 11
DIAGNOSIS AND TESTING (Continued)