Chevrolet 1977 light duty truck, Service Manual

Page: 211 / 861

Fig. 3B -1 4 -C h e ckin g H azard W a rning Flasher
First m ake these checks and replace any non­
operative components.
1.
Check
fu s e s (F ig u re 3B-12). Replace if blown. If
new fuse blows, replace flasher in system. (There are 2
flashers in the signal switch system. The hazard w arn in g
flasher and turn signal flasher are located on the fuse
block.
2. Check for secure connection at the chassis to
switch connector. This is the h arm o n ica connector on the
column (Figure 3B-13). Secure if loose. Check all
individual wire term inals for pro p er seating in the
connector bodies. T erm in als should be locked in place.
3. Depress h azard w arn in g button and check all
lights in signal swritch system. Replace any which do not
work. If all lamps light w h en hazard w arn in g is
depressed, but flashing does not occur, replace hazard
w a rn in g flasher. (On fuse block) (Figure 3B-14).
4. I f
all
directional lamps light w hen lane change
o r turn indicator is actuated, but no flashing occurs,
replace the turn signal flasher.
T h e above four steps will, in most cases, cure the
co m m o n signal switch system troubles. If the system is
still not o p e ra tin g correctly, use J-23980 to determ ine
w h e th e r the chassis w iring or the signal switch itself is at
fault.
M echanical
1. If the c u s to m e r ’s c o m p la in t indicates the
pro b lem is in the switch, function check as to return
from full left an d full right turns.
A ctuate the turn lever into a full turn position in
e ith e r direction, then tu rn the steering wheel (motor
on - pow er steering) at least 1/4 turn in the
direction indicated and then back to center. Do this
in both directions. If the lever does not retu rn to the
neutral position, disassemble the u p p e r p a rt o f the
column until the switch is visible.
2. Check the return from lane change by holding
the lever in lane change and releasing (both left and
right). If the lever does not return to neutral, disassemble
the upper part o f the column.
3. If the hazard w arn in g button cannot be
depressed or released, the switch must be replaced.
Switch Visual Inspection
1. With the u p p e r part o f the column disassembled
so that the signal switch is visible (Figure 3B-15) check
for missing springs. Replace any spring that is missing,
inspecting the molded pins which secure them. If these
pins are broken, the switch must be replaced.
2. Check the position o f the switch in the bowl. If
it appears cocked or crooked, loosen the securing screws
(3) and visually inspect the switch. If any o f the plastic is
broken or badly deform ed, the switch must be replaced.
3. If the switch appears undam aged, replace it
being careful to seat the pilot into the housing, tighten
the screws to 25 lbs. in. o f torque.
POW ER S TE ER IN G SYSTEM D IA G N O S IS
Com plaints o f faulty steering are frequently the
result o f problem s o th e r than the steering gear or pump.
Those areas o f the steering system which can be easily
checked and quickly corrected without disassembly and
overhaul o f any m ajor com ponents should be attem pted
first.
Conditions such as hard or loose steering, road
shock or vibrations are not always due to the steering
gear or pump, but are often related instead to such
factors low tire pressure and front end alignment. These
factors should be checked and corrected before any
L A N E C H A N G E
R E T U R N S P R I N G