2004 DAEWOO LACETTI ignition

HEATING AND VENTILATION SYSTEM 7A – 11
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
211. Disconnect the resistor block connector.
2. Connect one lead of a self–powered test light
to any single lead on the resistor block. Use
the other lead to probe each of the other two
terminals.
Does the test light illuminate on all terminals?–Go to Step 23Go to Step 22
22Replace the resistor block.
Is the repair complete?–System OK–
231. Turn the ignition to LOCK.
2. Disconnect the connector from the resistor
block.
3. Connect a jumper lead from the positive termi-
nal on the battery to any wire terminal in the
connector.
4. Use a 12–volt test light to check for voltage
from the corresponding wire on the blower
speed switch.
5. Repeat the same test on the other wires.
Does the lamp light on all three wires?–Go to Step 25Go to Step 24
24Replace the blower speed switch.
Is the repair complete?–System OK–
25Repair the open in the affected wire.
Is the repair complete?–System OK–
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
KnobTe m p
Contro
lBlower
Motor
SwitchBlower
SpeedPower
Vent
OutletFloor
OutletDefrost
OutletSide
Window
Outlet
VentColdOffOffNo
AirflowNo
AirflowNo
AirflowNo
Airflow
VentCold4HighAmbient
AirflowNo
AirflowNo
AirflowNo
Airflow
FloorCold to
Hot4HighNo
AirflowCold to Hot
AirflowMinimum
Cold to Hot
AirflowMinimum
Cold to Hot
Airflow
De-
frosterCold to
Hot4HighNo
AirflowMinimum
Cold to Hot
AirflowCold to Hot
AirflowMinimum
Cold to Hot
Airflow
If any of these settings does not produce the correct results, perform the following diagnostic procedure.

HEATING AND VENTILATION SYSTEM 7A – 13
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
151. Check for obstructions in the system at the
blower inlet and check the air filter if the vehicle
is so equipped.
2. Remove any obstructions at the blower inlet
and replace the filter if it is clogged.
Is the repair complete?–System OKGo to Step 16
161. 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 17Go to Step 18
171. Check the temperature door, the cable, the
linkage, and the control.
2. Adjust the temperature control to full hot.
Is the repair complete?–System OK–
181. 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–
TOO MUCH HEAT
StepActionValue(s)YesNo
1Verify the customer’s complaint.
Are the customer’s concerns verified?–Go to Step 2System OK
2Is there too much heat when the mode switch is in
the floor position?–Go to Step 3Go to Step 9
3Is there objectionable defroster bleed?–Go to Step 4Go to Step 5
41. Check the door travel, the cable, the vacuum
actuators, and the linkage for the heater and
the defroster.
2. Adjust or repair, as required.
Is the repair complete?–System OK–
51. In vehicles equipped with A/C, set the A/C
switch OFF.
2. In all vehicles, set the blower speed to maxi-
mum.
3. Set the temperature to full hot.
4. Turn the ignition switch ON.
5. Check for airflow from the floor outlets.
6. Check the floor outlet attachment.
Is the airflow high?–Go to Step 6Go to Step 8
6Check for a change in the airflow at different blower
speeds.
Does the airflow change as the setting for the blow-
er–speed switch is scanned?–Go to Step 7 Go to ”Blower
Electrical
(Manual and
Non–A/C)”

7A – 14IHEATING AND VENTILATION SYSTEM
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
71. Check the temperature door travel, the cable,
and the linkage.
2. Adjust to full cold.
3. Check for full hot.
Is the repair complete?–System OK–
8Adjust or repair the floor/defroster and/or the vent/
floor mode.
Is the repair complete?–System OK–
9In the vent position, is the problem objectionable
bleed?–Go to Step 10Go to Step 15
101. Check the system case for leaks.
2. Check the floor outlet attachment.
Are there problems?–Go to Step 11Go to Step 12
11Repair the system case or the floor outlet attach-
ment as required.
Is the repair complete?–System OKGo to Step 12
121. 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 reach the
end of the control travel?–Go to Step 13Go to Step 14
13Adjust the vent door to vent more.
Is the repair complete?–System OK–
141. Check the temperature door travel, the cables,
and the linkage.
2. Verify that the temperature door goes to full
cold.
3. Check the temperature door for full hot.
Is the temperature door travel correct?–System OK–
151. Set the fresh air/recirculating air control to
fresh air (indicator lamp off).
2. Set the temperature control to full cold.
3. Start the vehicle and allow the engine to warm
up.
4. Measure the air temperature at the blower in-
let, or cowl, and at the vent air outlet inside the
vehicle.
Is the outlet air more than 5°C (41°F) warmer than
the inlet air?–Go to Step 16System OK
161. Check for hot air leaks from the engine
compartment to the blower inlet.
2. Repair, as needed.
Is the repair complete?–System OK–

7A – 16IHEATING AND VENTILATION SYSTEM
DAEWOO V–121 BL4
BLOWER NOISE
StepActionValue(s)YesNo
1Verify the customer’s complaint.
Are the customer’s concerns verified?–Go to Step 2System OK
21. Sit inside the vehicle.
2. Close the doors and the windows.
3. Turn the ignition ON.
4. Start the engine.
5. Set the temperature to full cold.
6. Cycle through the blower speeds, the modes,
and the temperature settings in order to find
the noise.
Is the blower noise constant at high blower speeds
or certain modes, but absent at lower speeds or in
other modes?–Go to Step 11Go to Step 3
3Check for vibrations from the blower motor and fan
assembly at each blower speed by feeling the blower
motor housing.
Did you find excessive vibration?–Go to Step 6Go to Step 4
41. Remove the blower motor and the fan assem-
bly. Refer to ”Blower Motor” in this section.
2. Check for foreign material at the opening of the
blower inlet.
Do you find any foreign material at the blower inlet?–Go to Step 5Go to Step 6
5Remove all foreign material.
Is the repair complete?–System OKGo to Step 6
61. Examine the blower fan for wear spots,
cracked blades, a cracked hub, a loose fan re-
taining nut, or bad alignment.
2. Examine the blower case for wear spots.
Did you find any problem?–Go to Step 7Go to Step 9
7Repair as required.
Is the repair complete?–System OKGo to Step 8
8Replace the motor and the fan assembly.
Is the repair complete?–System OKGo to Step 9
9If the noise is a click/tick or whine, replace the motor.
Is the repair complete?–System OKGo to Step 10
10Reinstall the original motor.
Is the problem still present?–Go to Step 11System OK
111. Set the blower speed on maximum.
2. Check full–hot to full–cold temperature posi-
tions in the defrost, floor, and vent modes.
Is the noise present in the defrost mode only?–Go to Step 12Go to Step 13
121. Check the ducts for obstructions or foreign ma-
terials.
2. Remove any obstructions or foreign materials.
3. Check the floor/defroster door seals.
4. Repair or replace the components, as needed.
Is the repair complete?–System OK–
13Is the noise present in the floor mode only?–Go to Step 12Go to Step 14
14Is the noise present in the vent mode only?–Go to Step 15Go to Step 16

SECTION : 7B
MANUAL CONTROL HEATING, VENTILATION
AND AIR CONDITIONING SYSTEM
CAUTION : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool
or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help
prevent personal injury and damage to the vehicle. The ignition must also be in LOCK unless otherwise noted.
TABLE OF CONTENTS
SPECIFICATIONS7B–2 . . . . . . . . . . . . . . . . . . . . . . . . . .
General Specifications 7B–2. . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 7B–2. . . . . . . . . . .
SPECIAL TOOLS7B–3 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Tools Table 7B–3. . . . . . . . . . . . . . . . . . . . . . . .
SCHEMATIC AND ROUTING DIAGRAMS7B–6 . . . . .
A/C System – Typical 7B–6. . . . . . . . . . . . . . . . . . . . . .
Manual Control A/C Diagram 7B–7. . . . . . . . . . . . . . . .
DIAGNOSIS7B–8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DIAGNOSIS 7B–8. . . . . . . . . . . . . . . . . . . . . .
Testing the Refrigerant System 7B–8. . . . . . . . . . . . . .
Insufficient Cooling ”Quick Check” Procedure 7B–8. .
A/C Performance Test 7B–9. . . . . . . . . . . . . . . . . . . . . .
Pressure–Temperature Relationship of
R–134A 7B–10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Leak Testing Refrigerant System 7B–11. . . . . . . . . . . .
V5 SYSTEM AIR CONDITIONING DIAGNOSIS 7B–12
Insufficient Cooling Diagnosis 7B–12. . . . . . . . . . . . . .
SYMPTOM DIAGNOSIS 7B–16. . . . . . . . . . . . . . . . . . . .
Pressure Test Chart (R–134A System) 7B–16. . . . . .
Low and High Side Pressure Relationship
Chart 7B–18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE AND REPAIR7B–19 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 7B–19. . . . . . . . . . . . . . . . . . . .
GENERAL A/C SYSTEM SERVICE
PROCEDURES 7B–19. . . . . . . . . . . . . . . . . . . . . . . . . .
O–Ring Replacement 7B–19. . . . . . . . . . . . . . . . . . . . .
Handling Refrigerant 7B–19. . . . . . . . . . . . . . . . . . . . . .
Handling of Refrigerant Lines and Fittings 7B–19. . . .
Maintaining Chemical Stability in the Refrigeration
System 7B–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Discharging, Adding Oil, Evacuating, and Charging
Procedures for A/C System 7B–20. . . . . . . . . . . . . .
SERVICEABLE COMPONENTS 7B–23. . . . . . . . . . . . . Components Used In Non–A/C Systems 7B–23. . . . .
A/C Pressure Transducer 7B–24. . . . . . . . . . . . . . . . . .
A/C Compressor Relay 7B–24. . . . . . . . . . . . . . . . . . . .
Air Filter 7B–25. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A/C Expansion Valve 7B–25. . . . . . . . . . . . . . . . . . . . . .
A/C High–Pressure Pipe Line 7B–26. . . . . . . . . . . . . . .
Evaporator Core 7B–29. . . . . . . . . . . . . . . . . . . . . . . . . .
A/C Suction Hose Assembly 7B–30. . . . . . . . . . . . . . .
A/C Discharge Hose Compressor to
Condenser 7B–31. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Receiver–Dryer 7B–32. . . . . . . . . . . . . . . . . . . . . . . . . . .
Compressor 7B–33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Condenser 7B–35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 7B–37. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
COMPONENT LOCATOR 7B–37. . . . . . . . . . . . . . . . . . .
V5 Compressor 7B–37. . . . . . . . . . . . . . . . . . . . . . . . . . .
V5 AIR CONDITIONING COMPRESSOR
OVERHAUL 7B–38. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clutch Plate and Hub Assembly 7B–38. . . . . . . . . . . .
Clutch Rotor and Bearing 7B–40. . . . . . . . . . . . . . . . . .
Clutch Coil 7B–42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shaft Seal Replacement 7B–44. . . . . . . . . . . . . . . . . . .
Control Valve Assembly 7B–46. . . . . . . . . . . . . . . . . . .
Rear Head, Gasket, Valve Plate, Reed Plate,
and O–ring 7B–47. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cylinder to Front Head O–ring 7B–48. . . . . . . . . . . . . .
Leak Testing (External) 7B–50. . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION7B–51 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL INFORMATION 7B–51. . . . . . . . . . . . . . . . . .
The V5 A/C System 7B–51. . . . . . . . . . . . . . . . . . . . . . .
System Components – Functional 7B–51. . . . . . . . . .
System Components – Control 7B–52. . . . . . . . . . . . .
V5 Compressor – General Description 7B–52. . . . . . .
V5 Compressor – Description of Operation 7B–52. . .

7B – 12IMANUAL CONTROL HEATING, VENTILATION AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
V5 SYSTEM AIR CONDITIONING DIAGNOSIS
INSUFFICIENT COOLING DIAGNOSIS
Test Description
The numbers below refer to steps on the diagnostic table.
13. See the Important below.
32. See the Important below.Important : Perform this test under garage conditions with
the air temperature at 21–32°C (70–90°F), and no sun
load. Follow this test carefully for accurate results.
Important : Perform this test exactly as described to ob-
tain accurate results.
Step
ActionValue(s)YesNo
1Record the customer’s complaint.
Can you verify the customer’s complaint?–Go to Step 2System OK
21. Check the A/C fuse.
2. Check the blower fan operation.
3. Check the engine cooling fan operation.
4. Check the A/C compressor belt.
5. Check the A/C condenser for restricted airflow.
6. Check the clutch coil connection.
7. Repair or replace any components as needed.
8. Check the discharge air temperature with the
A/C turned ON.
Is the discharge air temperature normal?At least 7°C
(12°F) below
ambient air
temperatureSystem OKGo to Step 3
31. Turn the ignition switch to LOCK.
2. Connect the high– and the low–pressure
gauges.
Are both pressures within the value specified?69–345 kPa
(10–50 psi)Go to Step 4Go to Step 5
41. Check the A/C system for leaks.
2. Repair any refrigerant leaks as needed.
3. Recover, evacuate, and recharge the A/C sys-
tem.
4. Observe the two pressure gauges.
Are both pressures above the value specified?345 kPa
(50 psi)Go to Step 7–
5Observe the two pressure gauges.
Are both pressures below the value specified?69 kPa
(10 psi)Go to Step 6Go to Step 7
61. Add 0.45 kg (1 pound) of refrigerant R–134a.
2. Check the A/C system for leaks.
3. Repair any refrigerant leaks, as needed.
4. Recover, evacuate, and recharge the A/C sys-
tem.
5. Observe the two pressure gauges.
Are both pressures above the value specified?345 kPa
(50 psi)Go to Step 7–
71. Start the engine and allow it to run at idle.
2. Set the A/C controls to the following positions:
S The A/C switch to the ON.
S The fresh air control switch to fresh air (in-
dicator lamp OFF).
S The blower motor to 4.
S The temperature to full cold.
Does the A/C compressor clutch engage?–Go to Step 8Go to Step 10

MANUAL CONTROL HEATING, VENTILATION AND AIR CONDITIONING SYSTEM 7B – 13
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
81. Check for a knocking noise from the A/C com-
pressor.
2. Cycle the A/C compressor ON and OFF in or-
der to verify the source of the noise.
Do you hear a loud knocking noise?–Go to Step 9Go to Step 13
91. Recover the A/C system refrigerant.
2. Replace the A/C compressor.
3. Evacuate and recharge the A/C system.
4. Check the A/C system for leaks.
Is the compressor running normally?–Go to Step 13–
101. Turn the ignition switch to LOCK.
2. Disconnect the A/C compressor clutch coil con-
nector.
3. Connect a jumper wire from ground to one A/C
compressor clutch coil terminal.
4. Connect a fused jumper wire from the positive
battery terminal to the other A/C compressor
clutch coil terminal.
Does the A/C clutch engage?–Go to Step 11Go to Step 12
11Repair the electrical circuit to the A/C compressor
clutch coil.
Does the A/C clutch engage?–Go to Step 8–
12Replace the A/C compressor clutch coil.
Does the A/C clutch engage?–Go to Step 8–
131. Close all of the vehicle’s windows and doors.
2. Set the A/C controls to the following positions:
S The A/C switch to the ON position.
S The fresh air control switch to fresh air.
S The blower motor to 4.
S The temperature to full cold.
3. Start the engine and allow it to run at idle for 5
minutes.
4. Feel the evaporator inlet and outlet pipes.
Is there a noticeable difference in the temperature of
the evaporator inlet and outlet pipes?–Go to Step 15Go to Step 14
141. Turn the ignition switch to LOCK.
2. Recover the A/C system refrigerant.
3. Examine the high–pressure pipe for an ob-
struction.
4. Examine the expansion valve for an obstruction
or a malfunction.
5. Repair the obstruction or replace the expansion
valve as needed.
6. Evacuate and recharge the A/C system.
7. Check the A/C system for leaks.
8. Note the discharge air temperature with the
A/C ON.
Is the discharge temperature normal?At least 7°C
(12°F) below
ambient air
temperatureGo to Step 15Go to Step 13

7B – 14IMANUAL CONTROL HEATING, VENTILATION AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
151. Record the low– and the high–side pressures
after the A/C system has been operating for 5
minutes or more with the engine cooling fan
ON.
2. Locate the intersection of the low– and the high
side pressures. Refer to ”Low– and High–Side
Pressure Relationship Chart” in this section.
Do the low– and the high–side pressures intersect
in the white area of the chart?–System OKGo to Step 16
16Check the high– and the low–side pressures.
Do the low– and the high–side pressures intersect
in the grey area of the chart?–Go to Step 17Go to Step 20
17Feel the liquid pipe between the condenser and the
expansion valve.
Is the pipe cold?–Go to Step 18Go to Step 19
181. Examine the condenser for any restriction of
the airflow.
2. Check the cooling fans for proper operation.
3. Remove the restriction or repair the fans, as
required.
Is the pipe temperature normal now?At least 7°C
(12°F) below
ambient air
temperatureGo to Step 13–
191. Recover, evacuate, and recharge the A/C sys-
tem.
2. Check the A/C system for leaks.
Is the system free from leaks?–Go to Step 13–
20Observe the readings on the pressure gauges.
Are the A/C compressor high– and the low–side
pressures within the specified value of each other?207 kPa
(30 psi)Go to Step 21Go to Step 26
211. Run the engine at 3,000 rpm.
2. Set the A/C controls to the following positions:
S The A/C switch to the ON.
S The fresh air control switch to fresh air.
S The blower motor to 4.
S The temperature to full cold.
3. Close all of the vehicle’s windows and doors.
4. Turn the A/C switch ON and OFF every 20
seconds for 3 minutes.
Are the A/C compressor high– and the low–side
pressures within the specified value of each other?207 kPa
(30 psi)Go to Step 22Go to Step 13
22Observe the pressure rise on both gauges and the
temperatures of both the compressor suction pipe
and the discharge pipe.
Is the pressure rise on both gauges slow and the
suction pipe warm with the discharge pipe very hot?–Go to Step 25Go to Step 23
231. Turn the ignition switch to LOCK.
2. Make sure the compressor clutch is disen-
gaged.
3. Attempt to turn the clutch driver (not the
pulley).
Can you turn the clutch driver freely by hand?–Go to Step 25Go to Step 24