7B – 20IMANUAL CONTROL HEATING, VENTILATION AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
S Dip new O–rings in clean polyalkaline glycol refrig-
erant oil before installation.
MAINTAINING CHEMICAL STABILITY
IN THE REFRIGERATION SYSTEM
The efficient operation and the life of the air conditioning
(A/C) system is dependent upon the chemical stability of
the refrigeration system. When foreign materials, such as
dirt, air, or moisture, contaminate the refrigeration system,
they will change the stability of the refrigerant and the poly-
alkaline glycol (PAG) compressor oil. They will also affect
the pressure–temperature relationship, reduce efficient
operation, and can possibly cause interior corrosion and
abnormal wear of moving parts.
Observe the following practices to ensure chemical stabil-
ity in the system:
S Wipe away dirt or oil at and near any connection
before opening that connection. This will reduce the
chance of dirt entering the system.
S Cap, plug, or tape both sides of a connection as
soon as possible after opening the connection. This
will prevent the entry of dirt, foreign material, and
moisture.
S Keep all tools clean and dry, including the manifold
gauge set and all replacement parts.
S Use a clean and dry transfer device and container
to add polyalkaline glycol refrigerant oil. This will
ensure that the oil remains as moisture–free as
possible. Refer to ”Discharging, Adding Oil, Eva-
cuating, and Charging Procedures for A/C System”
in this section.
S Have everything you need ready to allow you to
perform all operations quickly when opening an A/C
system. Do not leave the A/C system open any lon-
ger than necessary.
S Evacuate and recharge any A/C system that has
been opened. Refer to ”Discharging, Adding Oil,
Evacuating, and Charging Procedures for A/C Sys-
tem” in this section for the instructions to perform
this procedure properly.
All service parts are dehydrated and sealed before ship-
ping. They should remain sealed until just before making
connections. All the parts should be at room temperature
before uncapping. This prevents condensation of mois-
ture from the air from entering the system. Reseal all parts
as soon as possible.
DISCHARGING, ADDING OIL,
EVACUATING, AND CHARGING
PROCEDURES FOR A/C SYSTEM
CAUTION : Use only refillable refrigerant tanks that
are authorized for the charging station being used.
The use of other tanks may cause personal injury or
void the warranty. Refer to the manufacturer’s in-
structions for the charging station.CAUTION : To avoid personal injury, always wear
goggles and gloves when performing work that in-
volves opening the refrigeration system.
A charging station discharges, evacuates, and recharges
an air–conditioning (A/C) system with one hookup. Filter-
ing the refrigerant during the recovery cycle together with
filtering during the evacuation cycle ensures a supply of
clean, dry refrigerant for A/C system charging.
S Never use the R–134a charging station on a sys-
tem charged with R–12. The refrigerants and the
oils from each system are not compatible with
those from the other system and must never be
mixed, even in the smallest amount. Mixing refriger-
ant residue will damage the equipment.
S Never use adapters which convert from one size
fitting to another. Such use allows contamination,
which may cause system failure.
Charging Station Setup and Maintenance
There are many charging stations available. All perform
the various tasks required to discharge the system and re-
cover refrigerant, evacuate the system, add a measured
amount of oil, and recharge an A/C system with a mea-
sured amount of refrigerant. Refer to the manufacturer’s
instructions for all initial setup procedures and all mainte-
nance procedures.
Control Panel Functions
A charging station will have controls and indicators to allow
the operator to control and monitor the operation in prog-
ress. Refer to the manufacturer’s instructions for details.
These can be expected to include the following:
1. Main Power Switch
S Supplies electrical power to the control panel.
2. Display
S Shows the time programmed for vacuum.
S Shows the weight of the refrigerant programmed
for recharging.
S Refer to the manufacturer’s instructions for de-
tailed programming information.
3. Low–Side Manifold Gauge
S Shows the system’s low–side pressure.
4. High–Side Manifold Gauge
S Shows the system’s high–side pressure.
5. Controls Panel
S Controls the various operating functions.
6. Low–Side Valve
S Connects the low side of the A/C system to the
unit.
7. Moisture Indicator
S Shows whether the refrigerant is wet or dry.
8. High–Side Valve
S Connects the high side of the A/C system to the
unit.
7D – 8IAUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
NO HOT AIR FROM BLOWER
StepActionValue(s)YesNo
1Check the coolant level.
Is the coolant level correct?–Go to Step 3Go to Step 2
2Add coolant as needed.
Is the heater operating?–System OKGo to Step 3
31. Turn the ignition to ON.
2. Observe the temperature indication screen of
the controller.
Does the digit flash on and off?–Go to Step 4Go to Step 5
4Run a self–diagnosis circuit check.
Does the display indicate a defect code?–Go to the table
for the code
that flashesGo to Step 7
5Observe the blower motor operation.
Is the blower motor functioning at all?–Go to Step 6Go to ”Blower
Motor Does
Not Run at All”
6Use the blower push switch to cycle the blower
through its different speeds.
Does the motor function at different speeds?–Go to Step 7Go to ”Code 6
– Power Tran-
sistor Error”
71. 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 9Go to Step 8
81. Remove the heater outlet and check for ob-
structions.
2. Remove any obstructions found.
Is the heater operating?–System OKGo to Step 9
9Observe the air mix door (AMD) motor 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 10Go to”Code 4 –
Air Mix Door
Error”
10Check the coolant hoses for leaks or kinks.
Are the coolant hoses in good condition?–Go to Step 12Go to Step 11
11Repair any problem with the coolant hoses.
Is the heater operating?–System OKGo to Step 12
12Check the surge tank cap.
Is the surge tank cap in good condition?–Go to Step 14Go to Step 13
13Repair or replace the surge tank cap as needed.
Is the heater operating?–System OKGo to Step 14
141. Set the A/C switch to OFF.
2. Set the temperature control to 32°C (90°F).
3. Set the blower motor speed to full high (all seg-
ments illuminated on the display).
4. Remove the surge tank cap.
5. Start the vehicle and run the engine at idle.
6. Watch for the flow of the coolant when the ther-
mostat opens.
Does the coolant flow?–Go to Step 16Go to Step 15
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
7D – 12IAUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM
DAEWOO V–121 BL4
BLOWER MOTOR DOES NOT RUN AT ALL
StepActionValue(s)YesNo
11. Turn the ignition to ON.
2. Observe the temperature indication screen of
the controller.
Does the digit go 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.–
3Check fuse F7 in the I/P fuse block.
Is this fuse in good condition?–Go to Step 5Go to Step 4
4Replace fuse F7.
Is the repair complete?–System OK–
5Check fuse EF3 in the engine fuse block.
Is this fuse in good condition?–Go to Step 7Go to Step 6
6Replace fuse EF3.
Is the repair complete?–System OK–
71. Turn the ignition switch to ON.
2. Measure the voltage between ground and ter-
minal 87(Violet) of the blower relay.
Is the voltage within the specified value?11–14 vGo to Step 15Go to Step 8
8Measure the voltage between ground and terminal
86 (Brown) at the blower relay.
Is the voltage within the specified value?11–14 vGo to Step 10Go to Step 9
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
AUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7D – 23
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
61. Reconnect the coolant temperature sensor to
the ATC harness.
2. Turn the ignition switch to ON.
3. Observe the temperature display area.
Does this display indicate the continuing presence of
a code 3 condition?–Go to Step 9System OK
71. Pull the ATC controller from the instrument
panel, leaving the wiring harness connected.
2. Measure the voltage between terminals A13
and B9 by backprobing the connectors.
Is the voltage equal to the value specified?< 4 vGo to Step 9Go to Step 8
81. Trace the wiring from controller terminals A13
and B9 to the coolant temperature sensor con-
nector terminals on the ATC harness connec-
tors.
2. Repair any open or high resistance found in the
wiring or connector terminals.
Is the repair complete?–System OK–
9Replace the ATC controller.
Is the repair complete?–System OK–
AUTOMATIC TEMPERATURE CONTROL HEATING, VENTILATION, AND AIR CONDITIONING SYSTEM 7D – 25
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
71. Remove the ATC controller from the instrument
panel.
2. Disconnect the harness connectors from the
ATC controller.
3. Examine the connector terminals on the har-
ness connectors and the controller connectors
and the harness wiring.
Is there a problem with any of these connectors or
the wiring?–Go to Step 8Go to Step 9
8Repair the problem found with a connector terminal
or wiring.
Is the repair complete?–System OK–
9Check continuity in the harness between the control-
ler connectors and the AMD motor connector.
S Controller terminal A2 to motor terminal 7.
S Controller terminal A8 to motor terminal 5.
S Controller terminal B6 to motor terminal 2.
S Controller terminal B5 to motor terminal 6.
S Controller terminal B4 to motor terminal 3.
Does the continuity equal the specified value? 0 ΩGo to Step 10Go to Step 11
10Repair the continuity problem.
Is the repair complete?–System OK–
111. Reconnect the AMD motor to the ATC harness.
2. Reconnect the ATC harness connectors to the
controller.
3. Turn the ignition to ON.
4. Use backprobing for voltage measurements.
5. Measure the voltage between ground and ter-
minal B5 at the controller.
Is the voltage equal to the specified value?< 4 vGo to Step 12Go to Step 14
121. Set the temperature controller to 18°C (64°F).
2. Connect a voltmeter between ground and ter-
minal A8 at the controller. It should display
about 12 v.
3. Raise the temperature setting on the controller
to 32°C (90°F).
Does the voltage equal the specified value?Drops from
12 v to 0 vGo to Step 13Go to Step 15
131. Connect a voltmeter between ground and ter-
minal A2 at the controller. It should display
about 12 v.
2. Change the temperature setting to 18°C
(64°F).
Does the voltage equal the specified value?Drops from
12 v to 0 vGo to Step 20Go to Step 15
141. Recheck the wiring harness and the connector
terminals associated with controller terminals
B4, B5, and B6, and AMD motor terminals 2, 6,
and 3.
2. Repair any problem found.
Is the repair complete?–System OK–
15Recheck all wiring circuits between the controller
and the AMD motor.
Is there a problem in the wiring or the connectors?–Go to Step 16Go to Step 17