Operator's Cab

Symptom Problem Solution

Drafts.

Poor air distribution.

Adjust directional air louvers.

Adjust heater control to a warmer position.

Set pressurizer blower switch to a lower position.

Improper door track adjustment.

Adjust door track.

Inadequate air flow.

Clogged air filters.

Clean filters.

Clogged air inlet screen.

Clean screen.

Heater core air flow restricted.

Clean evaporator and housing with compressed air.

Faulty blower fan motor.

See your John Deere dealer.

Defective blower fan switch.

See your John Deere dealer.

Loose wire connection.

Tighten wire.

Water leaking or dripping from heater core compartment.

Loose hose clamp.

Tighten clamp.

Ruptured heater hose.

Replace hose.

Broken heater core tubes.

Repair.

Drip pan dirty (AC).

Clean evaporator pan and outlet.

Drain tube plugged (AC).

Clean drain tube.

Pressurizer fan, windshield wiper and/or compressor will not operate.

Defective motor.

See your John Deere dealer.

Defective switch.

See your John Deere dealer.

Faulty wiring or loose connections.

Repair or replace wiring.

NX,9965,O18 -19-01DEC92-1/4


Symptom Problem Solution

Strange odors inside operator's cab.

Dirty air filter.

Clean filter.

Evaporator condenser pan dirty.

Clean pan and outlet.

Drain tube is plugged.

Clean drain tube.

Tobacco smoke and tar on evaporator exterior.

Clean filter.

Partial frosting and sweating of lines combined with poor cooling.

Compressor belt slipping.

Replace belt and/or pulleys (if worn).

Loss of refrigerant.

Check sight glass for bubbles and system for leaks. See your John Deere dealer.

Restricted or clogged liquid line.

See your John Deere dealer.

Expansion malfunctioning.

See your John Deere dealer.

Heater lines crossed.

See your John Deere dealer.

Ice flecks blowing from evaporator.

Control dial set too low.

Adjust the temperature control to a warmer position.

Insufficient blower speed.

Increase blower speed.

NX,9965,O18 -19-01DEC92-2/4


Symptom Problem Solution

Failure to cool.

Dirty air screen.

Clean screen.

Dirty air filters.

Clean filters.

Debris on radiator core or side screens.

Clean core screens.

Lint or dirt on condenser fins.

Blow out condenser fins with compressed air.

Refrigerant insufficient or extremely low.

See your John Deere dealer.

Loose compressor drive belt.

Tighten belt.

Heater on.

Turn heater off.

Heater lines crossed.

See your John Deere dealer.

Compressor clutch not engaging.

Check wiring or see your John Deere dealer.

Expansion valve not functioning.

See your John Deere dealer.

Restriction in refrigerant system.

See your John Deere dealer.

Loose wiring connector.

Tighten wire.

Defective temperature control switch.

See your John Deere dealer.

Outside temperature too low. (Below 70°F) (21°C).

Wait until day gets warmer. If there is a malfunction in system, see your John Deere dealer.

Condenser is overheating.

Clean condenser screens, cores and fins of condenser, oil cooler, and radiator

Severe restriction in high side.

See your John Deere dealer.

Burned out clutch field or faulty field.

See your John Deere dealer.

Short circuit in control circuit or failure of a switch in circuit.

See your John Deere dealer

NX,9965,O18 -19-01DEC92-3/4


Symptom Problem Solution

Hissing noise at expansion valve.

Loss of refrigerant.

Check sight glass for bubbles and system for leaks. See your John Deere dealer.

Restriction in refrigerant system.

Check for kinks in hoses.

Voltmeter needle in lower red band.

Plugged alternator.

Remove trash from exterior and interior of alternator screen.

Alternator not energized.

Check for voltage to alternator on purple wire with key ON, engine OFF.

Excess electrical loads.

Turn off lights. Reduce blower speed to medium or low. Clean air conditioner screens, cores, and filter.

Voltmeter needle in upper red band.

Alternator output too high.

See your John Deere dealer.

Heater will not shut off.

Heater hoses connected improperly. Defective heater control valve.

See your John Deere dealer.

Heater will not heat.

Air trapped in heater core.

Bleed the heater.

Defective thermostats in engine.

Replace the thermostats.

Air conditioner turned on.

Shut off air conditioner.

Defective heater control valve.

See your John Deere dealer.

Shut-off valves closed at engine.

Open valves.

Radio or cassette does not function.

Blown fuse.

Replace fuse.

Poor sound quality of cassette.

Oxide build-up on tape head.

Clean tape head.

Loss of high frequency response and increased background cassette.

Tape head magnetized.

Use demagnetizer. Keep magnetized tools away from tape head.

Slow or erratic operation of cassette.

Faulty tape cartridge.

Try other cartridges before contacting serviceman.

Automatic channel switch does not function.

Dirty channel switch contacts.

Clean with cleaning cartridge or isopropyl alcohol.

NX,9965,O18 -19-01DEC92-4/4