Barko Hydraulics 595ML, Руководство по обслуживанию

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page 56 595 ML CRL (S)
800-00177
AIR CONDITIONER MAINTENANCE CONTINUED...
Problem: Evaporator Core Icing Up (Freezing Up)
Evaporator Probe (2-pin black connector)
1. Set the control temperature to a low value. Verify that the compressor is on. Pull the probe and place is in a
bath of ice water. Compressor should turn off. If not, bump up the control temperature a few degrees and try
again.
2. Voltage between the two brown wires should be between 0 and 5 volts (5V when the sensor is not connected).
3. Resistance of evaporator probe sensor (Sensor unplugged). SEE CHART
4. If the probe functions properly but the core still freezes, reposition the tip of the probe to the coldest part of the
evaporator core.
Problem: No Heat Control (Make sure air temp sensor checks out – see above “Cab Temperature
Sensor”)
Water Valve (6-pin connector)
The water valve can be prone to jamming if the coolant loop has excessive contaminants in it. If the valve must be
replaced due to grit or debris preventing operation, flush the cooling system before replacing.
1. Checking water valve – with plug disconnected, apply 12 or 24 volts between pins 4 and 6 on the valve (the
empty cavity is between pins 4 and 6). The valve should move in one direction. Reverse voltage and the valve
should move in the opposite direction.
2. Check the wiring for good contacts.
3. The voltage between the orange and black wires (pins 6 and 4) should be + or – 12 or 24 volts depending on if
the valve is opening or closing. If the valve is not moving, the voltage will be at 0.
4. The voltage between the yellow and green wires (pins 2 and 3) should be 5 volts.
5. The voltage between the purple and green wires (pins 1 and 3) should be between 0 and 5 volts (5V when valve
is not connected).
6. If valve does not operate, replace valve. If power is not correct, check ECU.
Problem: No A/C
Clutch Power
1. If A/C clutch does not engage, check the red power wire to clutch relay.
2. Check clutch relay for engagement. Set the temperature control to a HIGH value and turn the defrost DEF
button on. The relay should engage. Turn the defrost button off and the relay should disengage. (Note: there may
be a few seconds of delay before engagement or disengagement).
3. The yellow wire to clutch relay grounds relay. Check that ECU is grounding yellow wire and relay operates.
Manually ground yellow to test relay.
Problem: Blower Fan Not Turning On
Blower Fan
1. If everything else works but the blower fan does not turn on, check the wiring. If the wiring is found to be good,
check for voltage on orange power wire to motor and check black ground wire for ground. If there is no voltage on
orange power wire, replace ECU.
2. If power is on orange power wire to motor, motor should operate. Test motor with independent power and
ground. If motor doesn’t operate with independent power and ground, replace motor. If motor does operate with
independent power, replace ECU.