Jeep 1996 Grand Cherokee Service Manual - page 357
The combination flasher cannot be repaired and, if
faulty, it must be replaced. Also, because of the com-
bination flasher’s active elements, it cannot be tested
with conventional automotive electrical test equip-
ment. If the flasher is believed to be faulty, test the
turn signal and hazard warning system circuits as
described in this group. Then, replace the combina-
tion flasher with a known good unit to confirm sys-
tem operation.
MULTI-FUNCTION SWITCH
The multi-function switch assembly is mounted to
the left side of the steering column (Fig. 1). This
switch contains circuitry for the following functions:
• Turn signals
• Hazard warning
• Headlamp beam selection
• Headlamp optical horn
• Windshield wipers
• Windshield washers.
The information contained in this group addresses
only the switch functions for the turn signal and haz-
ard warning circuits. For information relative to the
other switch functions, refer to the appropriate
group. However, the multi-function switch cannot be
repaired. If any function of the switch is faulty, the
entire switch assembly must be replaced.
TURN SIGNAL INDICATOR LAMPS
The turn signal indicator lamps are located in the
instrument cluster. They flash with the exterior turn
signal lamps to give the driver a visual indication
that a turn signal or the hazard warning system is
operating. For diagnosis and service of this compo-
nent, refer to Group 8E - Instrument Panel Systems.
VEHICLE INFORMATION CENTER
Models equipped with an optional Vehicle Informa-
tion Center (VIC) have a “turn signal on” warning
feature. The VIC module monitors the combination
flasher’s turn signal circuit. The VIC module will dis-
play the message, Turn Signal On, and send a chime
request signal to the Body Control Module (BCM) on
the Chrysler Collision Detection (CCD) data bus for a
single chime tone, if a turn signal remains activated
for more than approximately one-half mile of driving.
Refer to Group 8E - Instrument Panel Systems for
diagnosis and service of the VIC module. Refer to the
appropriate Body Diagnostic Procedures Manual for
diagnosis and service of the BCM or the CCD bus.
TURN SIGNAL LAMPS
The exterior lamps in the turn signal and hazard
warning circuits include the front park/turn signal,
the front side marker, and the rear tail/stop/turn sig-
nal. For diagnosis and service of these lamps, refer to
Group 8L - Lamps.
DIAGNOSIS AND TESTING
INTRODUCTION
When diagnosing the turn signal or hazard warn-
ing circuits, remember that high generator output
can burn out bulbs rapidly and repeatedly. If this is a
problem on the vehicle being diagnosed, refer to
Group 8C - Charging System for further diagnosis.
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
REFER TO GROUP 8M - PASSIVE RESTRAINT SYS-
TEMS
BEFORE
ATTEMPTING
STEERING
WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL COM-
PONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE
THE PROPER PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
TURN SIGNAL/HAZARD WARNING SYSTEM
WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS,
REFER TO GROUP 8M - PASSIVE RESTRAINT SYS-
TEMS
BEFORE
ATTEMPTING
STEERING
WHEEL,
STEERING COLUMN, OR INSTRUMENT PANEL COM-
PONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE
THE PROPER PRECAUTIONS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Turn the ignition switch to the On position.
Actuate the turn signal lever or hazard warning but-
ton. Observe the turn indicator lamp(s) in the instru-
ment cluster. If the flash rate is very high, check for
a turn signal bulb that is not lit. Replace that bulb or
repair the circuits to that lamp, as required. Test the
operation of the system again. If the turn indicator(s)
fail to light, go to Step 2.
Fig. 1 Multi-Function Switch
8J - 2
TURN SIGNAL AND HAZARD WARNING SYSTEMS
ZJ
DESCRIPTION AND OPERATION (Continued)