Daewoo MATIZ Service Manual page 758

7A – 8 HEATING AND VENTILATION SYSTEM
Step
1. Back flush the heater core.
2. Drain the cooling system.
3. Replace the coolant.
4. Warm the engine to an average operating
23
temperature.
5. Feel the heater inlet hose and the heater outlet
hose.
Is the heater inlet hose hot and the heater outlet
hose warm?
Replace the heater core.
24
Is the repair complete?
Recheck the system using the "Control
Settings/Correct Results" tests. Refer to ''Improper
25
Air Delivery or No Mode Shift" in this section.
Is the repair complete?
Check for airflow from the defroster or the vent
outlets.
26
Is there high airflow from the defroster or the vent
outlets?
Adjust the heater door at the floor and the vent door
to get the proper airflow.
27
Is the repair complete?
Switch the mode knob to defrost.
28
Is the defroster airflow OK?
1. Remove the heater outlet and check for
obstructions.
29
2. Remove any obstructions in the heater outlet.
Is the repair complete?
Check for airflow change at various blower speeds.
30
Does the blower speed increase as the control is
turned from 1 to 4?
Check for obstructions in the system at the blower
inlet.
31
Are there any obstructions?
Remove the obstructions in the system at the blower
inlet.
32
Is the repair complete?
1. Set the blower on 4.
2. Rotate the temperature control from full hot to full
cold.
33
3. Listen for an airflow change.
Does the airflow change?
Insufficient Heating or Defrosting (Cont'd)
Action Value(s) Yes
–
System OK
–
System OK
–
System OK
–
Go to Step 27
–
System OK
–
Go to Step 29
–
System OK
–
Go to Step 31
–
Go to Step 32
–
System OK
–
Go to Step 34
No
Go to Step 24
–
Go to Step 26
Go to Step 28
–
Go to Step 30
–
Go to ''Blower
Electrical''
Go to Step 33
–
Go to Step 35
DAEWOO M-150 BL2