TM 5-3805-280-24-1
Sub-System Diagnostics
NOTE: A diode can fail in two modes, either shorted or open. Continuity will be
FUEL SHUT-OFF
YES: If continuity is
measured in one direction only in a serviceable diode. Use "diode checking mode" on
SOLENOID HOLD-IN
measured in both checks,
meter when checking continuity.
COIL SUPPRESSION
diode has failed in a
DIODE (V8) AND FUEL
shorted mode. Replace.
SHUT-OFF SOLENOID
PULL-IN COIL
NO: If continuity is NOT
SUPPRESSION DIODE
measured in either check,
(V10) CHECK
diode has failed in an
open mode. Replace.
NO: If continuity is
measured in one check
and not the other, diode
T118385 UN21NOV98
is OK.
Remove diode from connector.
Connect an ohmmeter to diode terminals.
Is continuity measured?
9015
15
Reverse ohmmeter probes.
21
Is continuity measured?
1/1
YES: Solenoid is OK. Go
START-AID SOLENOID
IMPORTANT: DO NOT start engine with start aid can
to next check.
(Y4) CHECK
removed from solenoid. Dust can enter the engine,
seriously damaging the engine.
NO: Solenoid has failed.
Replace.
Disconnect harness from start-aid solenoid.
Remove ether can from start-aid
Connect 24 volts to solenoid terminal No. 1 and ground
T111034 UN21AUG97
terminal No. 2.
Does solenoid click?
Reconnect harness.
Replace ether can.
1/1
4-86