TM 9-2320-211-20
minal A. An indicator lamp in the end of the control
a. General Description. The electrical wiring of
lever is connected to terminal H and flashes on and
this vehicle is of waterproof construction. Where
off with the interrupted voltage.
m u l t i p l e connectors are necessary, they are the
s c r e w type, sealed by preformed packing on a
( 3 ) When the control lever is moved to in-
dicate a left turn, the flasher unit is energized as
s e a l e d composition connector. The electrical cir-
described (2) above. At the same time terminal H is
c u i t s are numbered in accordance with the ord-
connected to terminal C which connects to the left
nance system and can be identified from the
turn signal lamp via wire 22-461 and terminal B
d i a g r a m shown in figure 2-38. To establish con-
tinuity of any circuit, c h e c k w i t h s u i t a b l e t e s t
which connects to the left front turn signal lamp via
wire 461. The spotlight switch circuit (terminal D)
equipment, using the technique described in this
guide.
i s d i s c o n n e c t e d f r o m t h e l e f t stoplight circuit
(terminal C), and is connected only to the right
b. Directional Signal System.
stoplight circuit (terminal E) so the right stoplight
will function normally when the service brakes are
applied.
unit. The basic components consist of a directional
( 4 ) When the control lever is moved to in-
signal control assembly (mounted on the steering
dicate a right turn, the same action occurs except
column), a flasher unit, connecting cables, and four
that terminal E is connected to the right rear
lamps. The individual front lamps are contained in
stoplight via wire 22-460, and terminal A is con-
the park, turn, and blackout light assemblies
nected to the right front turn signal lamp via wire
mounted at the front of the vehicle. The rear lamps
460. The stoplight switch circuit [terminal D) is
are combined with the service stoplights and are
d i s c o n n e c t e d from t h e r i g h t s t o p l i g h t circuit
c o n t a i n e d in stoplight part and blackout marker
(terminal E) and connected only to the left
light assemblies at the rear of the vehicle.
stoplight circuit (terminal C) so the left stoplight
( 2 ) The system is energized by setting the
will function normally when the service brakes are
light switch to the stoplight position, which supplies
applied.
24 volts from terminal J via wire 460-461 to t e r -
( 5 ) When the control lever is moved to the
minal G of the directional signal control unit.
hazard warning position, all four lights (terminals
Moving the control unit lever to indicate a turn
A, B, C, and E) are connected to terminal H so that
connects terminal G to terminal F and supplies 24
all turn indicator lights on the vehicle (and trailer)
volts to the flasher unit. The flasher unit contains
w i l l f l a s h s i m u l t a n e o u s l y . In this position, the
e l e c t r o n i c circuitry which interrups this 24-volt
stoplight (terminal D) is disconnected completely,
current at a regular rate of - to one-second in-
since the vehicle is normally not driven with the
t e r v a l s . This interrupted voltage appears at ter-
hazard warning lights in operation.
Key to figure 2-38:
B. O. marker and parking light
A
H Dimmer switch
J
B
Horn
Headlights
Panel lights
K B. O. driving lights
C
D
L Circuit breakers
High beam indicator light
E
Light switch
M Horn button
F
Taillight and stoplight
N Stoplight switch
G
P Dash receptacle
Trailer connector receptacle
Circuit
Cable
No.
gage
Circuit
description
12
Regulator (shunt) to circuit breaker
10
C i r c u i t breaker to light switch (feed)
14
15
Light switch to dimmer switch
14
16
D i m m e r switch to headlights high beam and indicator.
14
17
D i m m e r switch to headlights lower beam
14
18
19
14
Light switch to B.O. driving light
Light switch to B. O. marker lights
14
20
21
Light switch to service taillight a n d trailer receptacle.
14
Light switch to service stoplight and trailer receptacle.
14
22
23
Light switch to B. O. stoplight and trailer receptacle.
14
Light switch to B. O. taillight and trailer receptacle.
14
24
C i r c u i t breaker to horn to horn button
14
25
14
C i r c u i t breaker to trailer receptacle (aux. power).
37
Light switch to instrument lights
40
14
14
Light switch to stoplight switch
75
90
14
T r a i l e r receptacle to ground
91
14
Headlight ground
490
B l a c k o u t clearance light
14
491
Light switch to parking lights
14
