2004 DAEWOO LACETTI sensor

SECTION : 7D
AUTOMATIC TEMPERATURE 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
SPECIFICATIONS7D–2 . . . . . . . . . . . . . . . . . . . . . . . . . .
Fastener Tightening Specifications 7D–2. . . . . . . . . . .
SCHEMATIC AND ROUTING DIAGRAMS7D–3 . . . . .
A/C Sensors/Defoggers and A/C Compressor
Controls Diagram 7D–3. . . . . . . . . . . . . . . . . . . . . . . .
A/C Blower and Motor Controls Diagram 7D–4. . . . . .
DIAGNOSIS7D–5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL A/C DIAGNOSTICS 7D–5. . . . . . . . . . . . . . .
V5 SYSTEM AIR CONDITIONING AND AUTOMATIC
TEMPERATURE CONTROL (ATC) 7D–5. . . . . . . . . .
Self–Diagnostic Circuit Check 7D–5. . . . . . . . . . . . . . .
Automatic Temperature Controller Does Not
Operate When Ignition Is ON 7D–6. . . . . . . . . . . . . .
Controller Does Not Illuminate When Light Switch
Is ON 7D–7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
No Hot Air From Blower 7D–8. . . . . . . . . . . . . . . . . . . .
No Cool Air From Blower 7D–10. . . . . . . . . . . . . . . . . .
Blower Motor Does Not Run At All 7D–12. . . . . . . . . .
Mode Control Do Not Work 7D–14. . . . . . . . . . . . . . . .
Air Source Selection Not Controlled 7D–16. . . . . . . . .
Compressor Magnetic Clutch Does Not
Engage 7D–17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DIAGNOSTIC TROUBLE CODES 7D–18. . . . . . . . . . . .
Code 1 – In–Car Sensor Error 7D–18. . . . . . . . . . . . .
Code 2 – Ambient Air Temperature Sensor
Error 7D–20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Code 3 – Water Sensor Error 7D–22. . . . . . . . . . . . . . .
Code 4 – Air Mix Door Error 7D–24. . . . . . . . . . . . . . . . Code 5 – Sun Sensor Error 7D–27. . . . . . . . . . . . . . . .
Code 6 – Power Transistor Error 7D–29. . . . . . . . . . . .
Code 7 – Max–Hi Relay Error 7D–31. . . . . . . . . . . . . .
MAINTENANCE AND REPAIR7D–32 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 7D–32. . . . . . . . . . . . . . . . . . . .
GENERAL A/C SYSTEM SERVICE
PROCEURES 7D–32. . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Service Procedures 7D–32. . . . . . . . . . . . . . .
SERVICEABLE COMPONENTS 7D–33. . . . . . . . . . . . .
Common HVAC Components 7D–33. . . . . . . . . . . . . . .
Automatic Temperature Control Assembly 7D–33. . . .
Inlet Air Door Motor 7D–34. . . . . . . . . . . . . . . . . . . . . . .
Mode Door Motor 7D–35. . . . . . . . . . . . . . . . . . . . . . . . .
Air Mix Door Motor 7D–35. . . . . . . . . . . . . . . . . . . . . . . .
Water Sensor 7D–36. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ambient Air Temperature Sensor 7D–36. . . . . . . . . . .
In–Car Temperature Sensor 7D–37. . . . . . . . . . . . . . . .
Sun Sensor 7D–37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 7D–39. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
V5 AIR CONDITIONING COMPRESSOR
OVERHAUL 7D–39. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Compressor Overhaul 7D–39. . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION7D–40 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL INFORMATION 7D–40. . . . . . . . . . . . . . . . . .
The V5 System 7D–40. . . . . . . . . . . . . . . . . . . . . . . . . . .
System Components – Control 7D–40. . . . . . . . . . . . .

AUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7D – 3
DAEWOO V–121 BL4
SCHEMATIC AND ROUTING DIAGRAMS
A/C SENSORS/DEFOGGERS AND A/C COMPRESSOR
CONTROLS DIAGRAM

AUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7D – 9
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
151. Check for
S A faulty thermostat.
S A failed coolant pump impeller.
S A restriction in the cooling system.
2. Make repairs as needed.
Is the repair complete?–System OK–
16Check the temperature of the heater inlet and outlet
hoses by feel.
Is the heater inlet hose hot and the outlet hose
warm?–Go to Step 18Go to Step 17
17Back flush or replace the heater core.
Is the repair complete?–System OK–
18Check the vehicle for cold air leaks at the
S Dash.
S Heater cases.
S Vents.
Are any leaks found?–Go to Step 20Go to Step 19
19Repair any cold air leaks.
Is the repair complete?–System OK–
20Check the coolant temperature sensor using the
tests in ”Code 3 – Coolant Temperature Sensor Er-
ror.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 21Go to Step 22
21Repair or replace the sensor, the wiring, or the con-
troller as required.
Is the repair complete?–System OK–
22Check the in–car sensor using the tests in ”Code 1
– In–Car Sensor Error.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 23Go to Step 24
23Repair or replace the sensor, the wiring, or the con-
troller as required.
Is the repair complete?–System OK–
24Check the ambient air temperature sensor using the
tests in ”Code 2 – Ambient Air Temperature Sensor
Error.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 25Go to Step 26
25Repair or replace the sensor, the wiring, or the con-
troller as required.
Is the repair complete?–System OK–
26Check the sun sensor using the tests in ”Code 5 –
Sun Sensor Error.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 27Go to Step 28
27Repair or replace the sensor, the wiring, or the con-
troller as required.
Is the repair complete?–System OK–
28Replace the ATC controller.
Is the repair complete?–System OK–

7D – 10IAUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
NO COOL AIR FROM BLOWER
StepActionValue(s)YesNo
11. Turn the ignition to ON.
2. Observe the temperature indication screen of
the controller.
Does the digit flash on and off?–Go to Step 2Go to Step 3
2Run a self–diagnosis circuit check.
Does the display indicate a defect code?–Go to the table
for the code
that flashes.Go to Step 7
3Observe the blower motor operation.
Is the blower motor functioning at all?–Go to Step 4Go to ”Blower
Motor Does
Not Run at All”
4Use the blower push switch to cycle the blower
through its different speeds.
Does the motor function at different speeds?–Go to Step 5Go to”Code 6 –
Power Transis-
tor Error”
51. Run the blower and operate the MODE push
switch manually.
2. Check for airflow out the various outlets.
Does the air flow from the different outlets as it
should?–Go to Step 7Go to Step 6
61. Remove the heater outlet and check for ob-
structions.
2. Remove any obstructions found.
Is the heater operating?–System OKGo to Step 9
7Observe the air mix door motor (AMD) while chang-
ing the temperature setting from 18 to 32°C (64 to
90°F) and then from 32 to 18°C (90 to 64°F).
Is the AMD motor functioning properly?–Go to Step 8Go to”Code 3 –
Air Mix Door
Error”
8Perform the checks found in ”Insufficient Cooling
Diagnosis.”
Is the system operating normally now?–System OKGo to Step 9
9Place the controller in the AUTO mode.
Is smoke taken into the intake port of the in–car sen-
sor?–Go to Step 12Go to Step 10
10Check the intake hose for the in–car sensor.
Is the hose in good condition?–Go to Step 12Go to Step 11
11Repair or replace the intake hose.
Is the repair complete?–System OK–
12Check the in–car sensor using the tests in ”Code 1
– In–Car Sensor Error.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 13Go to Step 14
13Repair or replace the sensor, the wiring, or the con-
troller as required.
Is the repair complete?–System OK–
14Check the ambient air temperature sensor using the
tests in ”Code 2 – Ambient Air Temperature Sensor
Error.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 15Go to Step 16

AUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7D – 11
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
15Repair or replace the sensor, the wiring, or the con-
troller, as required.
Is the repair complete?–System OK–
16Check the sun sensor using the tests in ”Code 5 –
Sun Sensor Error.”
Is there a problem indicated in the sensor, the sensor
wiring, or the controller?–Go to Step 17Go to Step 18
17Repair or replace the sensor, the wiring, or the con-
troller as required.
Is the repair complete?–System OK–
18Perform the coolant temperature sensor test.
Is the coolant temperature sensor malfunctioning?–Go to Step 19Go to Step 20
19Replace the coolant temperature sensor.
Is the repair complete?–System OK–
20Replace the ATC controller.
Is the repair complete?–System OK–

7D – 18IAUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODES
CODE 1 – IN–CAR SENSOR ERROR
This code will set if the output of the in–car sensor indicates a probable short circuit or an open in the sensor or the associat-
ed wiring harness, or a malfunction of the ATC controller.
Code 1 – In–Car Sensor Error
StepActionValue(s)YesNo
11. Disconnect the in–car sensor connector from
the ATC controller.
2. Examine the wiring from the sensor to the con-
nector and the connector for any signs of dam-
age.
3. Measure the resistance between the in–car
sensor connector terminals.
Is there any sign of damage in the wiring or connec-
tor, or is the resistance outside the specified value
at 20 to 25°C (68 to 77°F)?2600–2100 ΩGo to Step 2Go to Step 3
2Repair the damaged wiring or the connector, or re-
place the in–car sensor as required.
Is the repair complete?–System OK–
31. Turn the ignition to ON.
2. Measure the voltage between the two connec-
tor terminals on the controller housing.
Is the voltage equal to the value specified?> 4 vGo to Step 7Go to Step 4
4Check the terminals on the in–car sensor connector.
Is any problem found with the connector?–Go to Step 5Go to Step 6
5Repair the connector terminals or replace the in–car
sensor or ATC controller as required.
Is the repair complete?–System OK–

AUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7D – 19
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
61. Reconnect the in–car sensor to the controller.
2. Turn the ignition switch to ON.
3. Observe the temperature display area.
Does this display indicate the continuing presence of
a code 1 condition?–Go to Step 7System OK
7Replace the ATC controller.
Is the repair complete?–System OK–

7D – 20IAUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
CODE 2 – AMBIENT AIR TEMPERATURE SENSOR
ERROR
This code will set if the output of the ambient air temperature sensor indicates a probable short circuit or an open in the
sensor or the associated wiring harness, or a malfunction of the ATC controller.
Code 2 – Ambient Air Temperature Sensor Error
StepActionValue(s)YesNo
11. Disconnect the ambient air sensor connector
from the front bumper harness.
2. Measure the resistance between the ambient
air sensor connector terminals.
Is the resistance equal to the specified value at 20
to 25°C (68 to 77°F)?2600–2100 ΩGo to Step 5Go to Step 2
21. Remove the ambient air sensor from behind
the front bumper.
2. Examine the wiring for any open or short and
examine the connector for any damage.
Is there a problem with the wiring or the connector?–Go to Step 3Go to Step 4
3Repair the problem found in the ambient air sensor
wiring or the connector.
Is the repair complete?–System OK–
4Replace the ambient air sensor.
Is the repair complete?–System OK–
51. Turn the ignition to ON.
2. Measure the voltage between the two terminals
in the ambient air sensor connector on the front
bumper harness.
Is the voltage equal to the value specified?> 4 vGo to Step 7Go to Step 6
61. Reconnect the in–car sensor to the controller.
2. Turn the ignition switch to ON.
3. Observe the temperature display area.
Does this display indicate the continuing presence of
a code 2 condition?–Go to Step 8System OK