CHAPTER 2: VEHICLE MAINTENANCE INSTRUCTIONS
TM 9-2350-256-20
2-19 ELECTRICAL TROUBLESHOOTING- Continued
ENGINE MANIFOLD PREHEATER SYSTEM-Continued
WARNING
Remove all jewelry such as rings, dog tags,
bracelets, etc. If jewelry contacts a metal
surface a direct short may result in instant
heating of tools, damage to equipment, and
injury or death to personnel.
N Reconnect engine wiring harness to fuel solenoid.
Disconnect lead from spark plug. Hold lead close to
engine and turn MASTER switch on, push START and
manifold preheat switches, and check for spark. Turn
MASTER switch OFF. If spark is present, replace spark
plug (see paragraph 4-21). If spark is not present,
replace manifold preheater ignition unit (see paragraph 4-
19).
O Reconnect switch panel to neutral safety switch to
bulkhead harness to main switch panel. Disconnect
switch panel to gage panel and miscellaneous switches
wiring harness from main switch panel. Place red lead of
multimeter on pin M of wire 10 and black lead to ground.
Turn MASTER switch on push START switch, and check
for voltage. Turn MASTER switch OFF. If voltage is
present, go to step P. If voltage is not present,
troubleshoot battery circuit.
P Place a jumper wire from bracket to hull to ground the
panel. Reconnect switch panel and miscellaneous
switches
wiring
harness
to
main
switch
panel.
Disconnect wire 14 from START switch side of 20 A
circuit breaker. Place red lead of multimeter on terminal
of 20 A circuit breaker and black lead to ground. Turn
MASTER switch on and check for voltage. Turn
MASTER switch OFF. If voltage is present, go to step R.
If voltage is not present, go to step Q.
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