Jeep Cherokee
Service Manual
Electrically heated systems » Heated seat system » Diagnosis and testing
Heated seat system
For circuit descriptions and diagrams, refer to 8W -
63 - Power Seat With Heated Seats in Group 8W -
Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG
DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
The heated seat system is capable of performing
some self-diagnostics. The following table depicts the
various failure modes which will be reported to the
occupant via flashing the momentary switch telltales.
The switch telltales will flash on the driver's switch
if the failure exists in the driver's seat portion of the
system, similarly with the passenger's switch. The
telltale will illuminate for approximately a 1⁄2second
on, 1⁄2second off pulse for a duration of one minute.
This process will repeat every time the system is initiated
via the switches until the problem has been
corrected.
SEAT HEAT INTERFACE MODULE DIAGNOSTIC ROUTINES
Before testing the individual components in the
heated seat system, check the following:
- If the heated seat switch backlighting does not
illuminate with the ignition switch in the ON position,
check the fuse in the junction block. If the fuse
is OK, see Heated Seat Switch Backlighting in the
Diagnosis and Testing section of this group. If not
OK, repair the shorted circuit or component as
required and replace the faulty fuse.
- If the heated seat switch telltales do not illuminate
with the ignition switch in the ON position, but
the heating elements do heat, see Heated Seat
Switch Telltales in the Diagnosis and Testing section
of this group.
- If the heated seat switch backlighting illuminates
with the ignition switch in the ON position,
but the heating elements do not heat and the telltales
do not illuminate, check the circuit breaker in
the junction block. If the circuit breaker is OK, see
Heated Seat Switch Multiplexed Resistances in the
Diagnosis and Testing section of this group. If not
OK, replace the faulty circuit breaker.
- If the heated seat switch backlighting illuminates
and the telltales illuminate, but the heating
elements do not heat; see Heated Seat Element in
the Diagnosis and Testing section of this group.
More about «Diagnosis and testing»:
Heated seat system