2003 DAEWOO MATIZ heater

7A–6 HEATING AND VENTILATION SYSTEM
DAEWOO M-150 BL2
DIAGNOSTIC INFORMATION AND PROCEDURES
HEATER SYSTEM
INSUFFICIENT HEATING OR DEFROSTING
Caution: The cooling system is pressurized when hot. Injury can result from removing the surge tank cap
before the engine is sufficiently cool.
Step Action Value(s) Yes No

1

Verify the customer’s complaint.
Are the customer’s concerns verified?
–
Go to Step 2

System OK
2 Check the coolant level.
Is the coolant level correct? – Go to Step 4 Go to Step 3
3

Add coolant as needed.
Is the repair complete?
–

System OK

Go to Step 4
4

Check the timing belt for tension or damage.
Is the timing belt OK?
–

Go to Step 6

Go to Step 5

5

Correct any problem with the drive belts.
Is the repair complete?
–
System OK

Go to Step 6

6

Check the coolant hoses for leaks or kinks.
Are the coolant hoses OK?
–
Go to Step 8

Go to Step 7
7 Repair any problem with the coolant hoses.
Is the repair complete? –
System OK

Go to Step 8

8



Check the surge tank cap. Refer to Section 1D,
Engine Cooling.
Is the surge tank cap OK?


–


Go to Step 10


Go to Step 9

9


Repair or replace the surge tank cap as needed.
Is the repair complete?
–

System OK

Go to Step 10






10






1. Set the A/C switch OFF on vehicles equipped
with air conditioning.
2. Set the blower motor switch on 4.
3. Set the heater control to full hot.
4. Turn the ignition ON.
5. Check for airflow from the heater outlet.
Is there heavy airflow from the heater outlet?





–





Go to Step 11





Go to Step 25



11



Check for a change in the airflow at various blower
speeds.
Does the blower speed increase as the switch is
turned from 1 to 4?


–


Go to Step 12


Go to ‘‘Blower
Electrical’’








12








1. Set the A/C switch to OFF, on vehicles equipped
with air conditioning.
2. Set the temperature lever to full hot.
3. Set the blower motor switch on 4.
4. With the engine sufficiently cool, remove the
surge tank cap.
5. Start the vehicle and idle the engine.
6. Watch for the flow of the coolant.
Is the coolant flow visible?







–







Go to Step 14







Go to Step 13

HEATING AND VENTILATION SYSTEM 7A–7
DAEWOO M-150 BL2
Insufficient Heating or Defrosting (Cont’d)
Step Action Value(s) Yes No





13





1. Check for a

Restriction in the cooling system.

Failed water pump impeller.

Faulty thermostat.
2. Make repairs to the cooling system, as needed.
Are the repairs complete?




–




System OK





–






14






1. Check the vehicle for cold air leaks at the

Dash.

Heater cases.

Vents.
2. Check under the seat for obstructions.
3. Repair any leaks or obstructions.
Are the repairs complete?





–





System OK






–






15






1. Turn the ignition OFF.
2. Turn the temperature control knob to full cold,
then rapidly to full hot.
3. Listen for the sound of the temperature door slam
just before reaching the end of the travel range of
the control knob.
Did the door slam?





–





Go to Step 17





Go to Step 16







16







1. Check the temperature door

Travel.

Cables.

Linkage.
2. Verify the accuracy of the temperature controls at
full hot.
3. Verify the accuracy of the temperature controls at
full cold.
Is the repair complete?






–






System OK







–





17





1. Set the temperature door to full hot.
2. Start the vehicle.
3. Check the temperature of the heater inlet hose
and the heater outlet hose by feel.
Is the heater inlet hose hot and the heater outlet
hose warm?




–




Go to Step 18




Go to Step 21


18



Check the thermostat. Refer to Section 1D, Engine
Cooling.
Is the thermostat installed and seated properly?


–


Go to Step 19


Go to Step 20

19


Replace the thermostat. Refer to Section 1D, Engine
Cooling.
Is the repair complete?
–

System OK

–

20

Reinstall the thermostat.
Is the repair complete?
–

System OK

–

21


Inspect the heater hoses for proper installation.
Are heater hoses reversed?
–

Go to Step 22

Go to Step 23

22

Reinstall the heater hoses properly.
Is the repair complete?
–
System OK

–

7A–8 HEATING AND VENTILATION SYSTEM
DAEWOO M-150 BL2
Insufficient Heating or Defrosting (Cont’d)
Step Action Value(s) Yes No







23







1. Back flush the heater core.
2. Drain the cooling system.
3. Replace the coolant.
4. Warm the engine to an average operating
temperature.
5. Feel the heater inlet hose and the heater outlet
hose.
Is the heater inlet hose hot and the heater outlet
hose warm?






–






System OK






Go to Step 24
24

Replace the heater core.
Is the repair complete?

–

System OK

–




25




Recheck the system using the “Control
Settings/Correct Results” tests. Refer to ‘‘Improper
Air Delivery or No Mode Shift” in this section.
Is the repair complete?




–



System OK



Go to Step 26



26



Check for airflow from the defroster or the vent
outlets.
Is there high airflow from the defroster or the vent
outlets?


–


Go to Step 27


Go to Step 28

27



Adjust the heater door at the floor and the vent door
to get the proper airflow.
Is the repair complete?

–


System OK


–

28

Switch the mode knob to defrost.
Is the defroster airflow OK?
–

Go to Step 29

Go to Step 30




29




1. Remove the heater outlet and check for
obstructions.
2. Remove any obstructions in the heater outlet.
Is the repair complete?



–



System OK




–

30


Check for airflow change at various blower speeds.
Does the blower speed increase as the control is
turned from 1 to 4?
–

Go to Step 31

Go to ‘‘Blower
Electrical’’


31



Check for obstructions in the system at the blower
inlet.
Are there any obstructions?


–


Go to Step 32


Go to Step 33



32



Remove the obstructions in the system at the blower
inlet.
Is the repair complete?


–


System OK



–




33




1. Set the blower on 4.
2. Rotate the temperature control from full hot to full
cold.
3. Listen for an airflow change.
Does the airflow change?



–



Go to Step 34



Go to Step 35

HEATING AND VENTILATION SYSTEM 7A–11
DAEWOO M-150 BL2
IMPROPER AIR DELIVERY OR NO MODE SHIFT
This procedure provides a test of all functions of the heater/defroster unit.
1. Warm up the vehicle.
2. Keep the engine running.
3. Perform the tests outlined in the table below and look for the results indicated.
CONTROL SETTINGS CORRECT RESULTS



MODE
KNOB



TEMP.
CONTROL



BLOWER
MOTOR
SWITCH


BLOWER
SPEED



POWER
VENT
OUTLET


FLOOR
OUTLET



DEFROST
OUTLET



SIDE
WINDOW
OUTLET
Vent Cold Off Off No
Airflow No
Airflow No
Airflow No
Airflow



Vent

Cold

4

High

Ambient
Airflow
No
Airflow
No
Airflow
No
Airflow



Floor

Cold to Hot

4

High

No
Airflow
Cold to Hot
Airflow

Minimum
Cold to Hot
Airflow

Minimum
Cold to Hot
Airflow




Defroster


Cold to Hot


4


High



No
Airflow



Minimum
Cold to Hot
Airflow



Cold to Hot
Airflow



Minimum
Cold to Hot
Airflow
If any of these settings does not produce the correct results, perform the following diagnostic procedure.

Step

Action

Value(s)

Yes

No
1

Verify the customer’s complaint.
Are the customer’s concerns verified?

–

Go to Step 2

System OK




2





Examine the affected door in the unit for proper
cable attachment.

Check the cable connection to the door.

Check that the cable sheath is properly re-
tained.
Is the cable connected properly?




–




Go to Step 4




Go to Step 3
3

Repair as necessary.
Is the repair complete?
–

System OK

–





4





1. Disconnect the cable at the door.
2. Check the range of the door travel and the effort
required to move it.
Does the door move freely through its entire range
of travel so that it can close at both ends of the
range?




–




Go to Step 5




Go to Step 3

5


Check the travel of the Bowden cable by turning the
control knob.
Is the cable travel OK?
–

Go to Step 6

Go to Step 7



6




1. Reinstall the cable.
2. Recheck the system using the “Control
Settings/Correct Results” tests in this procedure.
Does the system perform properly?




–



System OK



Go to Step 9



7



1. Check the cable attachment at the control.
2. Check for a broken control.
Is there a problem with the cable attachment or the
control?


–


Go to Step 8


Go to Step 9

7A–12 HEATING AND VENTILATION SYSTEM
DAEWOO M-150 BL2
Improper Air Delivery or No Mode Shift (Cont’d)
Step Action Value(s) Yes No

8


Repair the cable attachment or control as necessary.
Is the repair complete?
–

System OK

Go to Step 9

9


Recheck the system using the “Control
Settings/Correct Results” tests in this procedure.
Is the repair complete?
–

System OK

Go to Step 10



10




Check for airflow from the defroster or the vent
outlets.
Is there high airflow from the defroster or the vent
outlets?



–



Go to Step 11



Go to Step 12

11


Adjust the heater door at the floor and the vent door
to get the proper airflow.
Is the repair complete?
–

System OK

–

12

Switch the mode knob to defrost.
Is the defroster airflow OK?
–

Go to Step 13

Go to Step 14




13




1. Remove the heater outlet.
2. Check the heater outlet for obstructions.
3. Remove any obstructions in the heater outlet.
Is the repair complete?



–



System OK




–

14

Check the blower speeds for change in the airflow.
Does the blower speed increase as the control is
turned from 1 to 4?
–
Go to Step 15

Go to ‘‘Blower
Electrical’’


15



1. Check for obstructions in the system at the
blower inlet.
2. Remove any obstructions at the blower inlet.
Is the repair complete?

–


System OK



Go to Step 16




16





1. Set the blower on 4.
2. Rotate the temperature control from full hot to full
cold.
3. Listen for an airflow change.
Did the airflow change?





–




Go to Step 17




Go to Step 18



17



1. Check the temperature door adjustment, the
cables, the linkage, and the control.
2. Adjust the temperature control to full hot.
Is the repair complete?


–


System OK



–




18




1. Check the system for any obstruction between
the blower and the system outlets.
2. Remove any obstruction between the blower and
the system outlets.
Is the repair complete?



–



System OK




–

HEATING AND VENTILATION SYSTEM 7A–13
DAEWOO M-150 BL2
TOO MUCH HEAT
Step Action Value(s) Yes No

1

Verify the customer’s complaint.
Are the customer’s concerns verified?
–
Go to Step 2

System OK

2


Set the mode switch to the floor position.
Is there too much heat when the mode switch is in
the floor position?
–

Go to Step 3

Go to Step 9
3

Check for defroster bleed.
Is there objectionable defroster bleed?
–

Go to Step 4

Go to Step 5



4




1. Check the door travel, the cables, the controls,
and the linkage for the heater and the defroster.
2. Adjust or repair, as required.
Is the repair complete?



–



System OK




–







5







1. In vehicles equipped with A/C, set the A/C switch
OFF.
2. In all vehicles, set the blower speed to 4.
3. Set the temperature to full hot.
4. Turn the ignition switch to ON.
5. Check for airflow from the floor outlets.
6. Check the floor outlet attachment.
Is the airflow high?







–






Go to Step 7






Go to Step 8



6




Check for a change in the airflow at different blower
speeds.
Does the airflow change as the setting for the
blower-speed switch is changed?



–



System OK




Go to ‘‘Blower
Electrical’’




7




1. Check the temperature door travel, the cables,
and the linkage.
2. Adjust to full cold.
3. Check for full hot.
Is the repair complete?



–



System OK




–

8


Adjust or repair the floor/defroster and/or the vent/
floor mode.
Is the repair complete?
–

System OK

–


9



Set the mode switch to the vent position.
In the vent position, is the problem objectionable
bleed?

–


Go to Step 10


Go to Step 15



10



1. Check the system case for leaks.
2. Check the floor outlet attachment.
Are any problems found?


–


Go to Step 11


Go to Step 12

11

Repair the system case or the floor outlet attach-
ment as required.
Is the repair complete?
–
System OK

Go to Step 12




12




1. Turn the ignition switch OFF.
2. Turn the temperature control knob to full hot, then
rapidly to full cold.
Do you hear the door slam just before you reached
the end of the control travel?



–



Go to Step 13



Go to Step 14
13

Adjust the vent door to vent more.
Is the repair complete?
–

System OK

–

7A – 18 HEATING AND VENTILATION SYSTEM
DAEWOO M-150 BL2
REPAIR INSTRUCTIONS
ON-VEHICLE SERVICE
D108A502
D108A501
CONTROL ASSEMBLY AND
CONTROL CABLES
(Left–Hand Drive Shown, Right–Hand
Drive Similar)
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the instrument cluster housing trim panel.
Refer to Section 9E, Instrumentation/Driver informa-
tion.
3. Remove the control assembly.

Remove the control assembly retaining screws (1).

Separate the control assembly from the instrument
panel (2).

Disconnect the electrical connectors (3).

Disconnect the mode control cable from the heater
module (4).

Disconnect the temperature control cable from the
heater module (5).

Remove the glove box from the instrument panel.
Refer to Section 9E, Instrumentation/Driver Infor-
mation.
D108A503

Disconnect the recirculating/fresh air door cable
from the blower module (6).

HEATING AND VENTILATION SYSTEM 7A–19
DAEWOO M-150 BL2
D108A504
D108A505
4. Disconnect the control cables from the control as-
sembly.

Disconnect the temperature control cable (1).

Disconnect the mode control cable (2).

Disconnect the recirculating/fresh air door cable
(3).
D108A506
Installation Procedure
1. Connect the control cables to the control assembly.
2. Connect the recirculating/fresh air door cable to the
blower module.
3. Install the glove box to the instrument panel. Refer to
Section 9E, Instrumentation/Driver Information.
4. Connect the temperature control cable and the mode
control cable to the heater module.
5. Connect the electrical connectors.
6. Install the control assembly with the screws.
7. Install the instrument cluster housing trim panel. Re-
fer to Section 9E, Instrumentation/Driver Information.
8. Connect the negative battery cable.