Diagnosis And Testing; Circuit Breaker - Jeep 1996 Grand Cherokee Service Manual

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DESCRIPTION AND OPERATION (Continued)
reversed through the switch contacts. This causes the
motor to run in the opposite direction.
The motor contains a self-resetting circuit breaker
to protect it from overload. Consecutive or frequent
resetting of the circuit breaker must not be allowed
to continue, or the motors may be damaged. Make
the necessary repairs. The motors used on models
with the optional memory system also have a posi-
tion potentiometer included in the motor assembly.
The power lumbar adjuster and motor cannot be
repaired, and are serviced only as a complete unit
with the seat back frame. If any component in this
unit should fail, the entire assembly must be
replaced.

CIRCUIT BREAKER

An automatic resetting circuit breaker in the junc-
tion block is used to protect the power seat system
circuit. The circuit breaker can protect the system
from a short circuit, or from an overload condition
caused by an obstructed or stuck seat adjuster. The
circuit breaker cannot be repaired. If faulty, it must
be replaced.

DIAGNOSIS AND TESTING

POWER SEAT SYSTEM
For circuit descriptions and diagrams, refer to
8W-63 - Power Seat in Group 8W - Wiring Diagrams.
Before any testing is attempted, the battery should
be fully-charged and all connections and pins cleaned
and tightened to ensure proper continuity and
grounds.
With the dome lamp on, apply the switch in the
direction of the failure. If the dome lamp dims, the
seat adjusters may be jamming. Check under and
behind the seat for binding or obstructions. If the
dome lamp does not dim, proceed with the following
component tests.
CIRCUIT BREAKER
For circuit descriptions and diagrams, refer to
8W-63 - Power Seat in Group 8W - Wiring Diagrams.
(1) Locate the correct circuit breaker in the junc-
tion block. Pull out the circuit breaker slightly, but
be sure that the terminals still contact the terminals
in the junction block.
(2) Connect the negative lead of a 12-volt DC volt-
meter to a good ground.
(3) With the voltmeter positive lead, check both
terminals of the circuit breaker for battery voltage.
If only one terminal has battery voltage, the circuit
breaker is faulty and must be replaced. If neither ter-
minal has battery voltage, repair the open circuit
from the power distribution center as required.
POWER SEAT SYSTEMS
POWER SEAT SWITCH
For circuit descriptions and diagrams, refer to
8W-63 - Power Seat in Group 8W - Wiring Diagrams.
To check the power seat switch:
(1) Remove the power seat switch as described in
this group.
(2) Use an ohmmeter to test the continuity of the
switches in each position. See the Power Seat Switch
Continuity chart (Fig. 1). If OK, see the affected
Power Adjuster/Motors diagnosis. If not OK, replace
the faulty switch module.
Fig. 1 Power Seat Switch Continuity
8R - 3