Tadano TT-800XXL1, Service Manual

Page: 185 / 267

K-2
K-2
Air Conditioner
32 W701-0160E
11.2 Car air conditioner system diagnosis table II (External causes other than insufficient cooling and abnormal pressure)
Trouble
phenomena
other than A/C
system
Disorder section
Phenomenon explanation to
consider other factors
Diagnosis result
(phenomenon of principal
cause)
Possible cause
Measures (specific part name
and repair method)
Water leak is
found. Cooling unit Leaks at normal operation. Water leak from cooling
case. Drain hose for blocking, bend, or
coming off failure.
Delivery valve blocking, bend,
coming off, or opening at end.
Blocking in outlet under case.
Crack under case. Install drain hose, grommets,
and heat insulators
appropriately, or replace case
and failed components.
Gas leakage sound is
heard. ------------------------------- Gas leakage between
evaporator unit and blower
motor heater unit. Seal with packing or packing
material.
------------------------------- Abnormal sound from motor or
bearing.
Replace the one with large
sound. Something is heard from
blower motor fan relation.
------------------------------- Foreign object intrusion in fan
case. Remove foreign object.
Refrigerant gas sound
(sound 'Goooo!') is heard. ------------------------------- Gas vibration sound (flow sound
or pulse sound)
Remove interference between
refrigeration piping and vehicle
frame or hood, if there is.
Whistle sound. ------------------------------- Replace parts for the one with
large whistle sound.
Gas flow sound may be
generated at insufficient
refrigerant or at air/refrigerant
mixed condition. Check refrigerant level, and
charge refrigerant.
Inside cabin.
Something is heard from
TXV relation (whistle sound
or gas flow sound).
Gas flow sound
------------------------------- Gas flow sound is generated
somewhat, and check sound
level, then replace if it is noisy.
------------------------------- Clutch bearing or idle pulley
bearing is failure.
Replace bearing and idle
pulley. Longevity will be
shortened if belt is
over-tensioned. Sound is generated when
compressor and
electromagnetic clutch are
OFF.
------------------------------- Loosening of idle pulley
mounting nut.
Re-tighten screw.
Noise sounds.
Engine room side
Sound is generated when
compressor starts. ------------------------------- Compressor noise failure. Repair or replace in case of
failure.