TM 5-3805-263-14&P-3
ELECTRICAL TROUBLESHOOTING
EMS PANEL
ELECTRONIC MONITORING SYSTEM
(11 to 170C) before the temperature sensor switch will
Operator Panel
deactivate (become not activated). If the coolant
temperature indicator does not go OFF in I 0 minutes,
The Electronic Monitoring System (operator panel)
shut off the engine. When the engine is cool, check the
gives information to the operator if there is a problem
coolant level.
with the machine. The Electronic Monitoring Panel has
If the hydraulic oil temperature indicator flashes and
indicators that flash (turn ON and OFF) when there is a
the coolant temperature indicator does not flash, the
problem. The Electronic Monitoring System also controls
hydraulic system is under too much load. Do not operate
a master fault light and fault alarm.
in a stall condition or at a high speed.
The panel indicators tell what the problem is. There
For the third level of warning, an indicator flashes,
are indicators for:
the master fault light flashes, and the fault alarm is
activated. This third level of warning is for low oil
1.
Low alternator output.
pressure, low brake air pressure and low fuel pressure.
2.
High engine coolant temperature.
(There is no flashing indicator for low fuel pressure on
3.
Low break air pressure.
the EMS panel.)
4.
Low engine oil pressure.
If the fault alarm is activated, the operator must shut
5.
High hydraulic oil temperature.
off the engine IMMEDIATELY.
6.
Steering.
Troubleshooting the operator warning system
(Electronic Monitoring System) is different than former
For the first level of warning only the indicator
systems that had indicator lights that were incandescent
flashes. This first level of warning is for low fuel level and
(light caused by heat). The indicators in the Electronic
low alternator output. If the alternator indicator flashes,
Monitoring System operator panel are light-emitting
there is low voltage output from the alternator, and the
diodes (LED's).
batteries will discharge if the air conditioner, lights, or
In former systems that used incandescent indicator
other accessories are ON. Check for a broken alternator
lights, the lights were turned ON when a sensor switch
belt. The machine can be operated until repairs can be
closed and made a ground for the light circuit. A
made to the charging system. If low fuel indicator
problem was shown if a switch closed and turned on the
flashes, the fuel level is below 10% full.
indicator light. If a harness connection be-came loose or
For the second level of warning, an indicator flashes,
a wire broke, between the indicator light and the sensor
and the master fault light also flashes. This second level
switch, the indicator light would not turn ON even if there
of warning is for high engine coolant temperature and
were a problem and the switch closed.
high hydraulic oil temperature.
If the coolant
In the Electronic Monitoring System, the sensor
temperature indicator flashes, the operator must put the
switches are closed when the operating conditions are
machine in a condition where it will become cooler. He
normal. The Electronic Monitor sees an open switch as
must:
an indication of a problem and turns on the correct
indicator. For some problems it also checks if the engine
1.
Stop the movement of the machine.
is running (fuel pressure switch). In this system, if a
2.
Lower any equipment to the ground.
harness connection becomes loose or a wire breaks, the
3.
Put the transmission in neutral.
Electronic Monitor sees it as an open circuit and flashes
4.
Engage the parking brake.
the indicator for that circuit. If an indicator flashes but the
5.
Decrease the engine speed to 3/4 of full speed.
problem shown by the indicator is not found, there could
be an open in the circuit between the sensor switch and
Check for coolant leakage, broken belts, or a
the Electronic Monitor, or between the sensor switch and
radiator core that has a restriction. It will take several
ground.
minutes before the coolant temperature indicator will turn
OFF because the temperature must go down 20 to 300F
4-20
