TM 5-3805-254-20-1
ORGANIZATIONAL TROUBLESHOOTING - CONTINUED
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
2. ENGINE CRANKS BUT FAILS TO START ABOVE 500F (180C) - CONTINUED.
WARNING
Although KEY SWITCH must be on and battery ground cable connected to test electrical circuit
voltage, turn off KEY SWITCH and disconnect battery ground cable before doing resistance tests
or replacing parts. This will keep you from getting shocked and prevent damage to parts and
equipment.
CAUTION
Do not crank engine for more than 20 seconds. Allow starter motor to cool for 2 minutes between
cranking attempts. Cranking too long can overheat and damage starter motor.
Step 10.
Check engine oil pressure switch (1) for 11 to 13 vdc as follows: Set multimeter to 20 vdc scale.
Connect red test lead to normally open (NO) terminal (2) and black test lead to ground. Have
assistant rotate KEY SWITCH (3) clockwise to on position and press ENGINE START button (4)
for 1 second. Check for 11 to 13 vdc on multimeter. Have assistant rotate KEY SWITCH (3)
counterclockwise to off position. Disconnect test leads.
a.
If multimeter reads no voltage, go to step 11.
b
If multimeter reads 11 to 13 vdc, to to step 12.
Step 11.
Check NO terminal (2) on engine oil pressure switch (1) and wires (5 and 6) for loose or corroded
condition.
a
If wires (5 and 6) are loose, tighten screw (7) using 3/16-inch flattip screwdriver.
b
If NO terminal (2) or wires (5 and 6) are corroded, loosen screw (7) and take off wires
(5 and 6) using 3/16-inch flat-tip screwdriver. Clean NO terminal (2) and wire
terminals on wires (5 and 6) using wire brush. Put wires (5 and 6) on NO terminal (2)
and tighten screw (7) using 3/16-inch flat-tip screwdriver.
c
If wires (5 and 6) or NO terminal (2) are not loose or corroded, go to step 13.
2-74
