TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
6.
INDICATOR/PANEL LIGHTS DO NOT OPERATE (MODEL A ONLY) (continued).
RELAY K4 TEST
(1) Remove four screws and
lockwashers from cab control
box.
(2) Remove six screws from cab
control box, and separate upper
body from base.
(3) Turn engine start switch to ON
UPPER
BODY
position.
(4) Turn light control switch to
STOP LIGHT position.
(5) Inspect whether LED D7 is on or
off.
(6) Turn engine start switch and
light control switch to OFF
position.
BASE
LED D7
4-119
Change 1
