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