TM 5-5420-226-20-1
Symptom-27
FROM STEP
o
2
:
DETAILED
TROUBLESHOOTING
PROCEDURE
VEHICLE
OPERATION
- HULL POWER
(Continued)
m
‘Check for electrical power to coil of master relay
(CKT459A).
Second Technician
(Operator’s
Station)
l Set MASTER BATTERY switch OFF.
First Technician
(Commander’s
Station)
l Remove floor access cover (page 17-9).
l Disconnect reverse polarity protection device connector
(CKT 459A) from master relay.
l Set meter to measure 18 to 30 volts dc, or use STE/ICE
Test No. 89 (page 4-81).
l Connect red probe of meter to center contact of reverse
polarity protection
device connector (CKT 459A) and
black probe to ground.
Second Technician
(Operator’s
Station)
l Set MASTER BATTERY switch ON.
First Technician
(Commander’s
Station)
l Check if meter indicates 18 to 30 volts dc.
m
Does meter Indicate 18 to 30 volts dc?
I
TO VEHICLE
GROUND
MASTER
REIAY
REVERSE
POLARITY
PROTECTION
DEVICE
(CKT 459A)
L
)
Replace master
relay
(page 10-138).
TA107O65
4-376
