TM 5-3805-262-20
3-11. LIGHT SYSTEMS TROUBLESHOOTING (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
8. SERVICE STOP LIGHTS DO NOT OPERATE (Cont).
S t e p 1 . ( C o n t ) .
c. If all lights are off, refer to page 3-81, MALFUNCTION 1.
Step 2.
Place vehicle lights switch in B.0. DRIVE position.
Tell assistant to press brake treadle and valve.
Blackout stop lights should be on.
a. If at least one blackout stop light is on, go to step 3 below.
b. If both blackout stop lights are off, refer to page 3-87, MAL-
FUNCTION 1.
Step 3.
Place vehicle lights and ignition key switches in off position.
Reach behind right instrument panel and unplug vehicle lights switch
connector by turning connector nut counterclockwise and pulling
f i r m l y.
Check wiring connection between wiring harness tan wire terminals at
stop and tail lights and vehicle lights switch connector pin C.
a. Repair or replace wiring or connector as necessary (page 5-168
or 5-174) .
b. If wiring and connectors are okay, remove right instrument panel
(page 5-48) and replace vehicle lights switch (page 5-53).
Step 4. Disconnect wiring harness tan wire terminal from tail light green
wire terminal by grasping both terminals with your fingers and firm -
ly pulling them apart.
Connect multimeter between wiring harness terminal and chassis
frame.
Tell assistant to press brake treadle and valve.
Multimeter should indicate 24 volts .
a . I f m u l t i m e t e r i n d i c a t e s 2 4 v o l t s, connect terminals by grasping
both terminals with your fingers, alining, and firmly pushing
them together. Then replace lamp (page 5-105). If stop light
still does not operate, go to step 5 below.
b . I f m u l t i m e t e r i n d i c a t e s z e ro , check wiring connection at green
wire terminal. Repair or replace wiring or terminal as necessary
(page 5-174).
3-89
