ELECTRICAL TROUBLESHOOTING
TM 5-3805-263-14&P-3
EMS PANEL
PROBLEM D: Fault Alarm is ON When It Must Be OFF.
Possible Causes: a.
Fuel pressure switch is bad (open when there is no pressure).
b.
A broken wire that goes to the fuel pressure switch.
c.
A short in the harness (wire to the fault alarm is shorted to a wire with +24V).
d.
Operator panel is bad
TROUBLESHOOTING
1. Remove the BR wire from the fuel pressure switch and connect it to machine ground.
Fault Alarm Stops
Fault Alarm Does Not Stop
Fuel pressure switch or ground wire to switch is bad.
Go to Step 3.
Go to Step 2.
2. Remove the B/W wire from the fuel pressure switch and check for continuity through
the switch with a continuity tester or a digital multimeter.
Continuity
No Continuity
Ground wire is bad. Replace the harness or connect a
Replace the fuel pressure switch.
ground wire to the switch.
3. Connect wires to fuel pressure switch again. Disconnect the harness plug from the
operator panel.
Fault Alarm Stops
Fault Alarm Does Not Stop
Go to Step 5.
There is a short in the plug or harness between wire to
connection 10 that sends power to the alarm and
another wire ( 1, 11 or 16) that has power. Go to Step 4.
4. Use a continuity tester or a digital multimeter to check for a short between 10 and 1
and between 10 and 11.
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