GMC 4000 Series Service Manual page 543

Sec. 12
Page 532
CHASSIS ELECTRICAL A N D INSTRUMENTS
DIRECTIONAL SIG N A L
C O N TRO L ASSEMBLY
CONTROL
LEVER
CO N TRO L TO
H O U S IN G SCREW
(O N E S H O W N )
DIRECTIONAL
H O U S IN G
Figure 21 — Directional Signal Control Assem bly
(with Hazard W arning Switch)
to remove control assem bly wiring from the w ir­
ing harness connector.
4. Remove screw attaching control lever to
switch and remove lever.
5. If hazard warning switch is mounted on side
of control housing, remove two screw s which at­
tach switch to housing.
6. Remove three screw s which attach control
assem bly to housing, then remove control assem ­
bly with wiring from housing.
INSPECTION
Inspect control switch, hazard switch (if used),
wiring and bearing. Replace worn or damagedparts.
Inspect cancelling cam on steering wheel hub and
replace if worn or damaged.
INSTALLATION (Fig. 20 or 21)
1. Position control assem bly in housing and
attach to housing with three screw s. Tighten screws
firm ly, however, do not exceed 30 inch-pounds
torque.
2. Position control lever on control assembly
and attach with screw . Tighten screw firmly.
3. If hazard warning switch was removed from
housing, position switch on housing and attach with
two screw s. Route switch wires on outside of con­
trol assem bly.
4. Connect w ires at harness connector.
5. Install steering shaft upper bearing sleeve,
then install steering wheel as directed under
"Steering Wheel Replacement" in "MECHANICAL
STEERING" (SEC. 9A) of this manual.
HAZARD W A R N IN G SYSTEM
All vehicles are equipped with a hazard warn­
ing or disability lighting system to be operated
G M C S E R V I C E M A N U A L
when on-the-road disability occurs. This system is
fed from the battery and can be operated regard­
SWITCH TO
le ss of ignition or control switch position.
H O U S IN G SC REW
/
"Wiring Diagrams" booklet for wiring arrange­
ment.
signal control housing or on the instrument panel
operates front and rear directional signal lights
simultaneously. When hazard warning or disability
lights are operating, the directional signal tell-tale
HAZARD lights or a light inside the switch knob will flash.
W A R N IN G
To cancel or "turn off" the lights, pull plunger out
SW ITCH
(or depress the knob).
HO RN RING A N D
B EARING ASSEMBLY
blown fuse or a defective flasher. If this fails to
correct the condition, replace the hazard warning
or disability lighting switch. The hazard warning
switch shown in figure 21 may be replaced as ex­
plained under "Directional Signal Control A ssem ­
bly" previously. To replace the dash-mounted-
type switch, remove the knob, then remove nut
attaching switch to dash panel. Pull switch from
dash panel and disconnect wiring harness. Install
new switch.
bulb in the switch knob, the bulb may be replaced
by removing the threaded knob.
load flashers are used in the directional and hazard
warning system on vehicles coveredby this manual.
Refer to "Specifications" at end of this section for
type of flasher and trade number.
flasher, the tell-tale will not operate if one direc­
tional lamp bulb is taken out of the circuit.
flasher, the directional tell-tale will operate even
though one or more of the indicator bulbs are
taken out of the circuit.
variable load flasher, each lamp bulb should be
checked daily for proper operation.
flashes in one position but not the other, check for
the following:
mounting.
sembly.
NOTE: Refer to Wiring Diagram in applicable
A switch mounted on side of the directional
If switch becomes inoperative, check for a
NOTE: On models which have an indicator
FLASHERS
Two or three prong specific load or variable
On vehicles equipped with the specific load
On vehicles equipped with the variable load
IMPORTANT: On vehicles equipped with the
If directional tell-tale on instrument panel
1. Directional lamp bulb burned out.
2. Incorrect directional lamp bulb installed.
3. Defective ground between bulb socket and
4. Defective directional control switch a s­