Monaco 2008 Knight, Руководство пользователя

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electrIcal systems - chassIs — 9
18
2 0 0 8 K n I G h t
Vacuum Generator - The vacuum
generator is important to the operation
of the dash heating and A/C systems.
This provides the vacuum to open
and close the vacuum switches. The
vacuum generator creates 15 inches of
vacuum that is passed to a reservoir
ball. Most dash heater and A/C systems
will only require 10 inches of vacuum
to operate the switches. The output
from the reservoir is sent to the vent
control knob. The control knob will
then direct the vacuum operation to
the appropriate vacuum switch to open
or close vents and switches. When the
ignition is on and the A/C is operating,
the vacuum generator will operate.
Troubleshooting
The dash A/C and Heat system uses a
combination of compressed air (developed by
the chassis system), vacuum air (developed by
the vacuum generator) and electric relays and
vacuum switches. Therefore, any repair can be
classified in one of five categories:
Electrical Vacuum
Air Conditioner
Heater
Defroster
No Cooling:
1. Check that the blower is operating, A/C
switch is in A/C or MAX A/C position,
temperature control is turned to MAX
cooling (blue area).
2. System fuses are not blown.
3. Condenser fan is operating.
4. Check power supply to unit and
grounding of system.
5. Check wiring.
6. Coolant valve is leaking.
7. Drive belt is loose or broken.
8. Compressor Clutch is inoperative, will
not engage.
9. Expansion Valve is faulty or frozen.
10. Thermostat control is faulty.
11. Mode control switch is faulty.
12. Compressor is faulty.
13. Loss of refrigerant.
NOTE
An ultraviolet or UV Blue Light cube
is used for leak detection when dye is
introduced to the A/C System.
Reduced Cooling:
1. Coolant valve not operating correctly.
2. Air passages are obstructed.
3. Loose or worn drive belt.
4. Check blower and select switch.
5. Thermostat control valve is faulty.
6. Expansion valve is faulty.
7. Compressor is faulty.
8. Low refrigerant charge.
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No Heating:
1. A/C switch is turned off.
2. Blower switch is turned off.
3. Verify the proper engine coolant level.
4. Verify that the engine is reaching
operating temperature.
5. Verify engine coolant is reaching water
valve attached to unit.
6. Verify operation of water valve to
permit engine coolant to pass through
valve to heater core.
7. Check unit fuses.
8. Check power supply to water valve and
grounding.
9. Check wiring.
10. Engine thermostat faulty.
Blower Does Not Operate or Runs Slow:
1. Check fuses.
2. Check for loose or corroded connection.
3. Check wiring.
4. Check to ensure ignition switch is on.
5. Check blower and select switch.
6. Motor shaft has seized.
7. Blower wheel is out of alignment.
Damper Doors DO NOT Operate:
1. Is the vacuum generator being powered
and producing a vacuum?
2. Check the vacuum line entering the unit
for vacuum.
3. Check that the vacuum solenoid
mounted on unit is receiving power
from the mode switch. If operating
properly, the vacuum solenoid will feel
hot if current is engaging the solenoid.
4. Check the mode switch.
5. Check wiring.
030947
Vacuum Generator: Located at front firewall.