Defrosting Insufficient; Heating Insufficient; Noise Diagnosis - Blower Motor - GMC chevrolet camaro 2000 Service Manual

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HVAC Heating, Ventilation and Air Conditioning
1-21
Defrosting Insufficient
1, Inspect for an obstruction in both of the defroster
nozzles.
Perform the following steps, as necessary:
• Remove any foreign objects.
• .Repair any loose instrument panel pad that
blocks an outlet.
2. Inspect for the proper operation of the defroster
air valve.
3. Inspect for one of the following conditions.
Replace the defroster vacuum actuator or hose if
one of the following conditions exist:
• A faulty defroster air valve vacuum actuator
• A faulty defroster air valve vacuum hose
4. Inspect for insufficient heating.
Refer to Heating Insufficient.
Heating Insufficient
1. Inspect the duct work for the following conditions:
• The proper installation
• Obstructions
2. Inspect the blower operation.
3. Inspect the following components for the proper
installation and the proper operation:
• The temperature lever
• The temperature motor
4. Inspect for the incorrect operation of the controls.
Advise the driver of the proper operation of the
controls.
5. Inspect the engine for low engine coolant level.
Perform the following steps, as necessary:
• Add coolant.
• Inspect the engine for coolant leaks.
• Run the engine in order to clear any air locks.
6. Inspect for a faulty engine thermostat.
Replace the thermostat, if necessary.
7. Inspect for a kinked heater hose.
Perform the following steps, as necessary:
'" Straighten tile heater hose.
• Replace the heater hose.
8. Inspect for obstructed heater core tubes.
An obstruction usually causes a squishing noise in
the heater core.
Perform the following steps, as necessary:
• Remove any foreign material from the
heater core.
• Replace the heater core.
9. Inspect for one of the following conditions:
• A faulty blower motor
Replace a faulty blower motor.
• A faulty blower circuit
Repair or replace faulty wires or connecUons.
Noise Diagnosis - Blower Motor
Step
Action Value(s) Yes No
DEFINITION: Noise originating from the blower motor and/or the air delivery system. No loss of battery or ground is
occurring in the blower motor circuit. The blower motor resistor and the blower motor are not exhibiting any intermittent
internal shorts. For electrical diagnosis of the blower motor circuit, refer to Blower Motor Inoperative at Any Speed in HVAC
Systems - Manual
Were you sent here from A Diagnostic System Check? Go to A
Diagnostic
1 -
System Check in
HV AC Systems -
Go to Step 2
Manual
1. Sit inside the vehicle.
2.
Close the vehicle doors and windows.
3. Turn the ignition switch to ON; engine OFF.
4. Turn the blower switch to position 5 (high).
5. Set the temperature control to full cold.
6. Set the mode control to UPPER (1/P outlets).
7. Cycle through all the blower motor speeds, modes
2
(including outside air and recirc) and temperature
control positions to determine where noise occurs
-
and where noise does not occur.
8. Attempt to define the type of noise:
• Scrape, pop
• Tick/click, chirping, groaning, scraping
• Air rush/whistle
Is a scrape or pop noise evident when selecting modes or
temperature settings (moving a mode or temperature
valve)?
Go to Step 12 Go to Step 3