
TROUBLESHOOTING
6.7
Cab Air Troubleshooting
Symptom
Problem
Solution
Section
Burned out motor
Burned out switch
Motor shaft tight or bearings
worn
Faulty wiring—loose or broken
Blower fan will not
run
Blower rotors in contact with
housing
Contact Dealer.
Contact Dealer
Dirty fresh air
fi
lter
Clean fresh air
fi
lter.
Cleaning Engine
Air Filter Primary
Element, page 343
Dirty recirculating air
fi
lter
Clean recirculating
fi
lter.
Cleaning Return
Air Cleaner, page
328
Evaporator clogged
Clean evaporator.
Cleaning Air
Conditioning (A/C)
Evaporator Core,
page 329
Blower fan
operating but no
air coming into cab
Air
fl
ow passage blocked
Remove blockage.
—
Heater shut-off valve at engine
closed
Open valve.
3.10.1 Heater
Shut-Off, page
56
Defective thermostat in engine
water outlet manifold
Replace thermostat.
Heater temperature control
defective
Replace control.
Heater not heating
No thermostat in engine water
outlet manifold
Install thermostat.
Contact Dealer
Plugged drainage hose
Blow out hose with compressed air.
—
Odor from air
louvers
Dirty
fi
lters
Clean
fi
lters.
Cleaning Engine
Air Filter Primary
Element, page
343
and
Cleaning
Return Air Cleaner,
page 328
147649
442
Revision A
Summary of Contents for M155
Page 3: ...Declaration of Conformity Figure 1 Declaration of Conformity Page 1 of 2 147649 i Revision A ...
Page 4: ...Figure 2 Declaration of Conformity Page 2 of 2 147649 ii Revision A ...
Page 30: ...SAFETY Figure 1 21 Safety Signs Left Cab forward Side 147649 14 Revision A ...
Page 32: ...SAFETY Figure 1 23 Safety Signs Right Cab forward Side 147649 16 Revision A ...
Page 44: ......
Page 54: ......
Page 320: ......
Page 414: ...MAINTENANCE AND SERVICING Fuse Box Decal Figure 5 178 Fuse Decal 147649 398 Revision A ...
Page 468: ......
Page 509: ......