DIAGNOSIS AND TESTING - TURN SIGNAL &
HAZARD WARNING SYSTEM
When diagnosing the turn signal and 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, be certain to
diagnose and repair the charging system as required.
If the problem being diagnosed is related to a failure
of the turn signals to automatically cancel following
completion of a turn, inspect the multi-function
switch for a faulty or damaged cancel actuator and
inspect the turn signal cancel cam on the clockspring
for damaged lobes or improper installation. The hard
wired circuits of the turn signal and hazard warning
system can be diagnosed using conventional diagnos-
tic tools and methods; however, for diagnosis of the
turn signal on warning feature, the use of a DRBIII
t
scan tool is required. Refer to the appropriate diag-
nostic information.
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFORE
ATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, SEAT BELT TENSIONER, OR INSTRU-
MENT PANEL COMPONENT DIAGNOSIS OR SER-
VICE. DISCONNECT AND ISOLATE THE BATTERY
NEGATIVE (GROUND) CABLE, THEN WAIT TWO
MINUTES FOR THE AIRBAG SYSTEM CAPACITOR
TO DISCHARGE BEFORE PERFORMING FURTHER
DIAGNOSIS OR SERVICE. THIS IS THE ONLY SURE
WAY TO DISABLE THE AIRBAG SYSTEM. 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 switch or the hazard warning
switch. Observe the turn signal indicator(s) in the
instrument cluster. If the flash rate is very high,
check for a turn signal bulb that is not lit or is very
dimly lit. Repair the circuits to that lamp or replace
the faulty bulb, as required. If the turn signal indi-
cator(s) fail to light, go to Step 2.
(2) Turn the ignition switch to the Off position.
Check the fused ignition switch output (run-acc) fuse
(Fuse 19 - 10 ampere) in the Junction Block (JB) and
the fused B(+) fuse (Fuse 1 - 30 ampere) in the
Power Distribution Center (PDC). If OK, go to Step
3. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse(s).
(3) Check for battery voltage at the fused B(+) fuse
(Fuse 1 - 30 ampere) in the PDC. If OK, go to Step 4.
If not OK, repair the open B(+) circuit between the
PDC and the battery as required.
(4) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-acc) fuse (Fuse 19 - 10 ampere) in the
JB. If OK, go to Step 5. If not OK, repair the open
fused ignition switch output (run-acc) circuit between
the JB and the ignition switch as required.
(5) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the combination flasher from the instrument
panel wire harness connector and replace it with a
known good unit. Reconnect the battery negative
cable. Test the operation of the turn signal and haz-
ard warning systems. If OK, discard the faulty com-
bination flasher. If not OK, remove the test flasher
and go to Step 6.
(6) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-acc) circuit cavity in the instrument
panel wire harness connector for the combination
flasher. If OK, go to Step 7. If not OK, repair the
open fused ignition switch output (run-acc) circuit
between the combination flasher and the fused igni-
tion switch output (run-acc) fuse (Fuse 19 - 10
ampere) in the JB as required.
(7) Turn the ignition switch to the Off position.
Check for battery voltage at the fused B(+) circuit
cavity of the instrument panel wire harness connec-
tor for the combination flasher. If OK, go to Step 8. If
not OK, repair the open fused B(+) circuit between
the combination flasher and the fused B(+) fuse
(Fuse 1 - 30 ampere) in the PDC as required.
(8) Disconnect the instrument panel wire harness
connector for the multi-function switch from the
switch connector receptacle. Check for continuity
between the hazard flasher signal circuit cavities in
the instrument panel wire harness connector for the
combination flasher and the instrument panel wire
harness connector for the multi-function switch.
There should be continuity. If OK, go to Step 9. If not
OK, repair the open hazard flasher signal circuit
between the combination flasher and the multi-func-
tion switch as required.
(9) Check for continuity between the right turn
switch sense circuit cavities in the instrument panel
wire harness connector for the combination flasher
and the instrument panel wire harness connector for
the multi-function switch. Repeat this check between
the left turn switch sense circuit cavities if these
same connectors. If OK, go to Step 10. If not OK,
repair the open right and/or left turn switch sense
8L - 4
LAMPS/LIGHTING - EXTERIOR
AN
LAMPS/LIGHTING - EXTERIOR (Continued)