215676
456
Revision A
Problem
Solution
Reference
Switch contacts in thermostat burned, or sensing
element defective
Replace thermostat.
Contact Dealer
Compressor partially or completely seized
Remove compressor for service or
replacement.
Contact Dealer
Condenser fins plugged
Clean condenser.
5.8.3 Air Conditioning
Condenser, page 338
Loose or broken compressor drive belt
Replace drive belt and/or tighten
to specifications.
Tensioning Air
Conditioner Compressor
Belt, page 383
and
Replacing Air Conditioner
Compressor Belt, page
383
Dirty filters
Clean fresh air and recirculation
filters.
Cleaning Engine Air Filter
Primary Element, page
353
and
Broken or disconnected electrical wire
Check all terminals for loose
connections; check wiring for
hidden breaks.
—
Broken or disconnected ground wire
Check ground wire to see if the
wire is loose, broken, or
disconnected.
—
Expansion valve stuck in open or closed position
Contact Dealer.
Contact Dealer
Broken refrigerant line
Contact Dealer.
Contact Dealer
Leak in system
Contact Dealer.
Contact Dealer
Compressor shaft seal leaking
Contact Dealer.
Contact Dealer
Clogged screen in receiver-drier; plugged hose or coil
Contact Dealer.
Contact Dealer
Symptom: Air conditioning not producing sufficient cooling
45
Compressor clutch slipping
Remove clutch assembly for
service or replacement.
Contact Dealer
Thermostat defective or improperly adjusted
Replace thermostat.
Contact Dealer
Clogged air filters
Remove air filters, and clean or
replace as necessary.
Cleaning Engine Air Filter
Primary Element, page
353
and
Heater circuit is open
Close temperature control in cab,
and valve on engine.
3.10.3 Climate Controls,
page 54
and
Insufficient air circulation over condenser coil; fins
clogged with dirt or insects
Clean condenser.
5.8.3 Air Conditioning
Condenser, page 338
Evaporator fins clogged
Clean evaporator fins (under cab
floor).
Cleaning Air Conditioning
Evaporator Core, page
339
45. Sufficient cooling defined as when air temperature in cab, measured at louvered vent, can be maintained at 14°C
(25°F) below ambient air temperature.