TM 5-5420-234-14&P
4-12. UNIT TROUBLESHOOTING (continued).
15. LHS DOES NOT OPERATE PROPERLY IN AUTO MODE (CAB ONLY)
(continued).
UPPER
BODY
VOLTAGE 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.
CAUTION
Use care when removing relay
from circuit board. Failure to
comply with this caution may
result in damage to circuit board.
(3) Remove relay K8 from cab control
box circuit board.
(4) Turn engine start switch to ON
position.
BASE
(5) Turn light control switch to STOP
LIGHT position.
(6) Set multimeter to voltage position.
NOTE
A reading of infinity indicates an
open circuit.
This test can also be
accomplished by observing the
status of LED D28.
(7) Connect one multimeter lead to
terminal 86 of relay K8 socket and
the other multimeter lead to a
RELAY (K8)
known good ground. Check
SOCKET
multimeter for voltage.
4-325
