Chevrolet 1980 Light Duty Truck Service Manual page 227

C O N D ITIO N
Hazard switch will not
stay on or difficult
to turn off
No turn signal lights
Turn indicator lights
on, but not flashing
SIG NAL SWITCH DIAG NO SIS
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
B. Loose chassis to
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
E. If the vehicle's lights
do not operate,
check light sockets
for high resistance
connections, the
chassis wiring for
opens, grounds, etc.
Fig. 3B 4-1 4 -T u rn Signal Sw itch Diagnosis C h art B
STEERING CO LUM NS
CORRECTION
A.
Tighten mounting
screws (25 in-lbs)
B.
Remove interference
C. Remove foreign
material
D. Replace switch
A. Replace fuse and
check operation
B. Replace turn signal
flasher
Connect securely,
C.
check operation
D. Replace signal switch
E. Repair chassis wiring
as required using
manual as guide
A. Replace turn flasher
Note: There are two
flashers in the system.
Consult manual for location.
B. Connect securely
and check operation
C. Replace turn signal
switch
D. Replace signal switch
E. Repair chassis wiring
as required using
manual as guide
LIG H T T R U C K SER V IC E M AN UAL
3B 4-13