OPERATOR'S STATION
TM 5-3805-263-14&P-3
PROBLEM A: All Indicators, Master Fault Light, and Fault Alarm OFF.
Possible Cause:
system voltage is over 36 volts.
TROUBLESHOOTING
1. Check system voltage with a digital multimeter.
Voltage Greater Than 36V
Voltage Less Than 36V
Repair or replace the alternator and regulator.
Do TEST I again.
PROBLEM B: Fault Alarm Does NOT Turn ON.
Possible Causes: a.
Fuel pressure switch that controls fault alarm is bad.
b.
Wire from operator panel to fuel pressure switch is grounded.
c.
Fault alarm is bad.
d.
Wire from operator panel to fault alarm has an open or a ground.
e.
Operator panel is bad.
The fuel pressure switch controls the operation of the fault alarm. When the engine is
in operation and the fuel pressure is high enough, the fuel pressure switch opens.
When the fuel pressure switch is open, the fault alarm can be activated if the test
switch is in the TEST position or if one of the indicators is ON that calls for the fault
alarm to also be ON.
TROUBLESHOOTING
1. Disconnect the BR wire from the fuel pressure switch. The fault alarm must be
activated (same as an open switch) with the test switch in the TEST position.
Fault Alarm Turns On
Fault Alarm Does Not Turn ON
Replace the fuel pressure switch.
Go to Step 2.
2. Check for a ground in the wire from the operator panel to the fuel pressure switch.
Disconnect the harness plug from the operator panel.
Leave the BR wire
disconnected from the fuel pressure switch.
Check for continuity between connections 2 and 13 with a continuity tester or a digital
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