TM 5-3895-367-14&P
Table 4-2. UNIT TROUBLESHOOTING (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 5.
Check voltage as follows for each inoperative
lamp until problem is isolated:
a.
Connect wiring harness to towing
vehicle.
b.
Remove lens from each light assembly.
NOTE
The only wires used are the ones illustrated. All other
wires are cut.
COLOR DESCRIPTION
Green
Backup
Red
Service taillight
White
Right hand service signal
Yellow
Left hand service signal
Black
Ground
c.
Refer to wiring diagram. Connect red
multimeter lead to terminal for
inoperative lamp. Connect black
multimeter lead to ground.
d.
Apply power as appropriate (turn on
light, apply brakes).
If no
voltage is present, replace or repair
wiring harness (para 4-17).
If
voltage is present, proceed to Step
e.
e.
Remove lamp from socket. Connect
red multimeter lead to lamp socket and
black lead to ground. Apply power as
appropriate (turn on light, apply brakes).
If no
voltage is present, replace light
assembly (para 4-16).
3.
DIM OR FLICKERING LIGHTS.
Step 1.
Check wiring harness for loose connections
and broken wires.
Tighten loose
connections. Replace or repair wiring
harness (para 4-17).
Step 2.
Check ground lead for continuity as follows:
a.
Disconnect wiring harness from towing
vehicle.
b.
Remove lens from each light assembly.
c.
Connect multimeter red lead to harness
connector pin D. Connect black lead to
end of ground lead.
If
continuity is not present, replace
wiring harness (para 4-17). If
continuity is present, reconnect
ground lead.
Step 3.
Check electrical leads for continuity as follows:
a.
Remove lens from each light assembly.
b.
Refer to wiring diagram. Check each
lead for continuity.
If
continuity is not present in any lead,
replace wiring harness (para 4-17).
If continuity is present in all leads,
replace light assembly (para 4-16).
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