TM 9-2320-211-20
tightened securely. Replace the circuit breakers or
l i g h t switch and tighten t h e b a t t e r y c a b l e s a s
required.
d. Directional Signal System Circuit (figure 2-
NOTE
Before starting tests, make a thorough
visual inspection for loose connection, poor
ground or
frayed
cables.
Make
all
necessary repairs before proceeding.
(1) Test 1. Perform the lamp continuity test.
Set the main light switch to the STOPLIGHT
position. Try all positions of the directional signal
control lever, and observe which lights do not light
i n any position of the lever. Have an assistant
depress the brake pedal and observe the stoplights,
If the stoplights light, the rear lamps are
operational. If the stoplights do not light, or if the
front turn indicators do not light in any position of
the control lever, turn the light switch to the OFF
p o s i t i o n and disconnect connector 460, 461, 22-
460, or 22-461, corresponding to the defective light
the
up
Set
for a continuity test. Clip the black test lead to the
vehicle frame. Touch the red test lead to the
connector on the light as shown in figure 2-40.1,
test 1. If the meter needle deflects to approximately
(2) Visually check the lights for proper
5 ohms, the lamp is normal and the trouble is
operation.
e l s e w h e r e . If the meter does not deflect at all
(3) Actuate the dimmer switch for headlight
(infinity reading), replace the lamp and re-test. If
operation and again visually check for proper
the meter still shows infinity or considerably more
operation.
than 5 ohms, touch the red test lead to the frame
(4) If one headlight will not operate but the
ground making sure to scrape through the paint to
o t h e r units will, the problem is not in the light
the bare metal. If the meter does not deflect
switch or circuit breakers. Replace the lamp unit or
completely to zero ohms, inspect the ground
check for a loose ground connection and tighten if
connection by removing the wire and scraping all
necessary. C h e c k and replace wiring harness as
metal surfaces bright, and reconnecting. When the
required.
light has been restored to 5 ohms, reconnect the
(5) If all of the light units are inoperative, the
connector and test the directional system again. If
problem could be in the circuit breakers or the light
the trouble still exists, perform the wire harness
switch. Also, check to see that the battery cables are
tests.
