Chevrolet LIGHT DUTY TRUCK (SERIES 10-35) Service Manual page 248

CONDITION
Hazard switch will not
stay on or difficult
to turn off
No turn signal lights
Turn indicator lights
on, but not flashing
SIGNAL SWITCH DIAGNOSIS
POSSIBLE CAUSE
A.
Loose switch
mounting screws
B. Interference with
other components
C. Foreign material
D. None of the above
A. Defective or
blown fuse
B. Inoperative turn signal
flasher
C. Loose chassis to
column connector
D. Disconnect column
to chassis connector.
Connect new switch
to chassis and
operate switch by
hand.
If vehicle lights now
operate normally,
signal switch is
inoperative
E. If vehicle lights do
not operate check
chassis wiring for
opens, grounds, etc.
A. Inoperative turn
♦ flasher
Loose chassis to
B.
column connection
Inoperative turn
C.
signal switch
To determine if turn
D.
signal switch is
defective, substitute
new switch into
circuit and operate
switch by hand.
If the vehicle's lights
operate normally,
signal switch is
inoperative
If the vehicle's lights
E.
do not operate,
check light sockets
for high resistance
connections, the
chassis wiring for
opens, grounds, etc.
Fig. 3 B 4 - 1 4 ~ T u r n S ig n a l S w it c h D ia g n o sis C h a r t B
STEERING COLUMNS
CORRECTION
A. Tighten mounting
screws (25 in-lbs)
B. Remove interference
C. Remove foreign
material
Replace switch
D.
A. Replace fuse and
check operation
Replace turn signal
B.
flasher
Connect securely,
C.
check operation
Replace signal switch
D.
E. Repair chassis wiring
as required using
manual as guide
Replace turn flasher
A.
Note: There are two
flashers in the system.
Consult manual for location.
Connect securely
B.
and check operation
Replace turn signal
C.
switch
D. Replace signal switch
Repair chassis wiring
E.
as required using
manual as guide
LIGHT TR U CK SER V IC E MANUAL
3B4-13