Chevrolet 1977 light duty truck Service Manual page 213

C O N D ITIO N
Hazard switch w ill not
stay on o r d iffic u lt
to tu rn o ff
No tu rn signal lights
T u rn indicator lights
on, but not flashing
SIGNAL SWITCH DIAGNOSIS
POSSIBLE CAUSE
A. Loose switch
m ounting screws
B. In terference w ith
other com ponents
C. Foreign m aterial
D. None o f th e above
A. D efective or
b lo w n fuse
B. In o p erative tu rn signal
flasher
C. Loose chassis to
colum n connector
D. Disconnect colum n
to chassis connector.
C onnect new switch
to chassis and
operate switch by
hand.
If vehicle lights now
operate n o rm a lly ,
signal switch is
inoperative
E.
If vehicle lights do
not operate check
chassis w irin g fo r
opens, grounds, etc.
A . Ino p erative turn
.flasher
B. Loose chassis to
colum n connection
In o p erative tu rn
C.
signal switch
T o determ in e if turn
D.
signal switch is
defective, substitute
new switch into
circu it and operate
switch by hand.
If th e vehicle's lights
operate n o rm ally,
signal switch is
inoperative
E. If th e vehicle's lights
do not operate,
check light sockets
fo r high resistance
connections, the
chassis w irin g fo r
opens, grounds, etc.
CORRECTION
A. T ighten m ou n ting
screws (2 5 in-lbs)
B. Remove interference
Remove foreign
C.
m aterial
D. Replace switch
A. Replace fuse and
check operation
Replace tu rn signal
B.
flasher
C. Connect securely,
check operation
D. Replace signal switch
E. Repair chassis w iring
as required using
manual as guide
Replace tu rn flasher
A .
N ote: There are tw o
flashers in th e system.
Consult manual fo r location.
B. Connect securely
and check operation
Replace tu rn signal
C.
switch
D. Replace signal switch
Repair chassis w iring
E.
as required using
manual as guide