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
MANUAL CONTROL HEATING, VENTILATION AND AIR CONDITIONING SYSTEM 7B – 17
DAEWOO V–121 BL4
Test ResultsRemedy Probable Cause Related Symptioms
Suction pressure ab-
normally highSuction pressure is lowered
when the condenser is
cooled by water.Excessive refrigerant in the sys-
tem.Recover, evacuate, and re-
charge the system.
High and low pressure are
equalized as soon as the
compressor is stopped and
both gauges fluctuate while
the compressor is running.Faulty gasket.Repair or replace the com-
pressor.
Faulty high–pressure valve. (V5
compressor only)
Foreign particles stuck in the
high–pressure valve. (V5 com-
pressor only)
Suction and dis-
charge pressure ab-
ll hi h
Reduced airflow through
the condenser.Clogged condenser or radiator
fins.Clean the condenser and
the radiator.
g
normally highRadiator cooling fans working im-
properly.Check the voltage and the
radiator cooling fan rpm.
Check the fan direction.
Condenser is excessively
hot.Excessive refrigerant in the sys-
tem.Recover, evacuate, and re-
charge the system.
Suction and dis-
charge pressure ab-
normally lowLow–pressure hose and
metal end areas are cooler
than the evaporator.Clogged or kinked low–pressure
hose.Repair or replace the low–
pressure hose.
Temperature around the ex-
pansion valve is low
compared to that around
the receiver–dryer.Clogged high–pressure line.Repair or replace the high–
pressure line.
Refrigerant leaksThe compressor clutch is
dirty.Leaking compressor shaft seal.Repair or replace the com-
pressor.
The compressor bolts are
dirty.Leaking around a compressor
housing bolt.Tighten the bolt(s) or re-
place the compressor.
The compressor gasket is
wet with oil.Leaking compressor gasket.Repair or replace the com-
pressor.
MANUAL CONTROL HEATING, VENTILATION AND AIR CONDITIONING SYSTEM 7B – 21
DAEWOO V–121 BL4
Refrigerant Recovery
Important : Use only a refrigerant tank that is designed for
the charging station in use. The unit’s overfill limitation
mechanism is calibrated specifically for use with this tank.
The tank’s valves are also manufactured specifically for
this unit.
1. Attach the high–side hose with the quick disconnect
coupler to the high–side fitting of the vehicle’s A/C
system.
2. Open the coupler valve.
3. Attach the low–side hose with the quick disconnect
coupler to the low–side fitting of the vehicle’s A/C
system.
4. Open the coupler valve.
5. Check the high–side and the low–side gauges on
the unit’s control panel in order to ensure that the
A/C system has pressure. If there is no pressure,
there is no refrigerant in the system to recover.
Important : If there is no refrigerant in the system, do not
continue with the recovery operation which would, under
this condition, draw air into the recovery tank.
6. Open both the high–side and the low–side valves.
7. Open the gas and the liquid valves on the tank.
8. Drain any oil that may be in the oil separator.
9. Close the oil drain valve.
10. Plug the unit into the proper voltage outlet.
11. Turn on the main power switch.
Notice : Never reuse refrigerant oil. Damage to the A/C
system may result from such reuse. Dispose of the refrig-
erant oil properly.
12. Begin the recovery process. Refer to the manufac-
turer ’s instructions for the charging station in use.
Important : Some A/C system polyalkaline glycol (PAG)
lubricating oil may be removed with the refrigerant during
recovery. The amount of oil removed varies. A charging
station separates the oil from the refrigerant and provides
a means of determining how much oil was removed. Re-
place the same amount of oil when recharging the system.
Refer to the manufacturer’s instructions for the charging
station in use.
13. Wait 5 minutes, then check the control panel low–
side gauge. If the A/C has maintained vacuum, the
recovery is complete.
14. If the low–side gauge pressure rises above zero,
there is more refrigerant in the system. Recover the
additional refrigerant. Repeat this step until the sys-
tem maintains vacuum for 2 minutes.
Important : If the control indicator shows that the refriger-
ant tank is full during the recovery process and the unit
shuts off, install an empty unit tank to store the refrigerant
needed for steps later in the procedure. Do not use any
other type of tank.
Evacuation
The unit tank must contain a sufficient amount of R–134a
refrigerant for charging. Check the amount of refrigerant
in the tank. If there is less than 3.6 kg (8 pounds) of refrig-
erant, add new refrigerant to the tank. Refer to the
manufacturer ’s instructions for adding refrigerant.
1. Verify that the high–side and the low–side hoses
are connected to the A/C system. Open both the
high–side and the low–side valves on the unit’s
control panel.
2. Open both the gas and the liquid valves on the
tank.
Important : Refer to the manufacturer’s instructions for
the charging station in use. It is necessary to evacuate the
system before recharging it with new or recycled refriger-
ant.
3. Start the vacuum pump and begin the evacuation
process. Non–condensable gases (mostly air) are
vented from the tank automatically during the re-
cycling process. You may hear the pressure being
released.
4. Check for leaks in the system. Refer to the
manufacturer ’s instructions for the charging station
in use.
Important : Change the vacuum pump oil frequently. Re-
fer to the manufacturer’s instructions for the charging sta-
tion in use.
A/C System Oil Charge Replenishing
Any oil removed from the A/C system during the recovery
process must be replenished at this time.
1. Use the correct graduated bottle of PAG oil for the
R–134a system.
Important:
S Keep the oil bottles tightly capped at all times to
protect the oil from moisture and contamination.
S You must have an A/C system vacuum for this op-
eration. Never open the oil injection valve while
there is positive pressure in the A/C system. This
will result in oil blowback through the bottle vent.
S Never let the oil level drop below the pickup tube
while charging or replenishing the system, as this
will allow air into the A/C system.
2. Refer to the manufacturer’s instructions for the
charging station in use. Add the proper amount of
PAG oil to the system.
3. Close the valve when the required oil charge has
been pulled into the system.
Charging
Important : Evacuate the A/C system before charging.
1. Close the low–side valve on the control panel.
2. Open the high–side valve on the control panel.
3. Refer to the manufacturer’s instructions for the
charging station in use.
4. Enter the amount of refrigerant needed to charge
the A/C, making sure to use the correct system of
measurement, i.e. kilogram (kg) or pound (lb).
5. Begin the charging process.
9E – 2IINSTRUMENTATION/DRIVER INFORMATION
DAEWOO V–121 BL4
SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Air Deflector Screws2–18
Chime Module Screws4–35
Clock Screws2–18
Cupholder Screws2.5–22
Deposit Box Screws2.5–22
Driver Knee Bolster Bolts10–89
Floor Console Brace Bolts4–35
Floor Console Brace Nuts4–35
HVAC Controls Screws4–35
Instrument Cluster Screws4–35
Instrument Cluster Trim Panel Screws4–35
Instrument Panel End Bolts2015–
Instrument Panel End Screws4–35
Instrument Panel Nuts Above the Steering Column2015–
Instrument Panel Bolts Behind the HVAC Controls4–35
Steering Column Bracket Nut2216–
Steering Column Lower Trim Cover Screws2.5–22
Steering Column U–Clamp Nuts2216–
Steering Column Upper Trim Cover Screws3–27
INSTRUMENT CLUSTER INDICATOR LAMPS
SPECIFICATIONS
Indicator LampColorBulb
ABS WarningAmber14 v 1.4 W
Airbag WarningRed14 v 1.4 W
Battery Charge IndicatorRed14 v 1.4 W
Check EngineAmber14 v 1.4 W
Door Open WarningRed14 v 1.4 W
Engine OverheatRed14 v 1.4 W
Fasten Seat Belt WarningRed14 v 1.4 W
High Beam IndicatorBlue14 v 1.4 W
Low Fuel Level WarningAmber14 v 4 W
Oil Pressure WarningRed14 v 1.4 W
Parking Brake Indicator and Brake Fluid WarningRed14 v 1.4 W
Service Engine Soon WarningAmber14 v 1.4 W
Transaxle Power Mode IndicatorAmber14 v 1.4 W
Turn Signal IndicatorsGreen14 v 1.4 W
9K – 2ISQUEAKS AND RATTLES
DAEWOO V–121 BL4
Glass Knock Coming From the Rear of the Vehicle When Driving
Over Bumps
ChecksAction
Check for an out–of–adjustment hatchback latch.S Test drive the vehicle in order to verify this condition.
S Loosen the latch nuts and adjust the latch downward.
Rattle Coming From Door
Checks Action
Check the door lock solenoid.S Remove the door trim panel and check if the sole-
noid is loose.
S Tighten the solenoid bolts.
Check for rattling electrical connectors inside the door trim
panel.S Tap on the trim panel and listen for a rattle.
S Remove the trim panel and wrap foam padding
around the connectors as required.
Squeak When Operating Doors
ChecksAction
Check for a lack of lubrication of the door hinge pins.S Operate the doors and listen for squeaks.
S Lubricate the door hinge pins with light oil and coat
with lithium grease.
Squeak Coming From Console When Shifting Manual Transaxle
(Condition Occurs In Cold Weather with a Cold Engine)
Checks Action
Check the manual transaxle control lever lower boot.S Move the control lever between gears and listen for
squeaks.
S Remove the floor console and replace the lower shift
boot or apply talcum powder to the lower shift boot.
Buzz From the Left Side of Instrument Panel
ChecksAction
Check for vibration of the fuse box cover against the instru-
ment panel side trim.S Tap on the cover with a finger and listen for a buzz.
S Apply 6.35 mm (0.250 inch) by 25.4 mm (1.00 inch)
felt pads to the side trim where the cover makes con-
tact.
Squeak Coming From Instrument Cluster Trim Plate
Checks Action
Check for rubbing of the cluster trim plate on the instru-
ment panel.S Test drive the vehicle in order to verify this condition.
S Remove the instrument cluster trim plate and install
felt tape to the edges.
9T2 – 8IIMMOBILIZER ANTI–THEFT SYSTEM
DAEWOO V–121 BL4
KEY STATUS ERRORS (MR–140,
HV–240, SIRIUS D4)
The following KEY STATUS messages may be shown on
the scan tool after commanding FIRST KEY CODING and
KEY ADD:
S IGNITION OFF STATUS. This message informs
the technician that the ignition is off during the key
coding process. Turn the ignition ON during key
coding, but do not start the engine.
S KEY IS OCCUPIED. Only five keys may be coded.
If a new key is desired, the previous key codes
must be deleted. Up to five keys may then be au-
thorized.
S ALREADY AUTHORIZED. Key coding is being at-
tempted with a key that is already authorized.
S ERROR NO. A3, A4, A5. There is no communica-
tion between the transponder in the ignition key and
the detection coil. Follow the steps below to diag-
nose the problem:
1) Try a different key. If a different key works, the
problem was in the original key.
2) If trying a different key resulted in the same
error message, replace the detection coil.
S INVALID KEY. The communication between the
immobilizer control unit and the key transponder
has not validated the key. Follow the steps below to
diagnose the problem:
1) Code the key. Refer to ”Key Coding Procedure”
in this section.
2) If the same message is received after key cod-
ing, check the connection of the detection coil.
3) If the detection coil is okay, replace the immo-
bilizer. Refer to ”Immobilizer Control Unit” in
this section.S NO TRANSPONDER DETECTED. The fault may
be in ignition key transponder, the detection coil, or
the Immobilizer. Follow the steps below to diagnose
the problem:
1) Try a different key. If a different key works, the
problem was in the original key.
2) If trying a different key resulted in the same
error message, check the connection of the
detection coil.
3) If the connection of the detection coil is okay,
disconnect the detection coil and use an ohm-
meter to check for an open detection coil.
4) If the detection coil was not open, replace the
immobilizer control unit. Refer to ”Immobilizer
Control Unit” in this section.
COMMUNICATION BETWEEN
IMMOBILIZER CONTROL UNIT AND
TEST EQUIPMENT (MR–140, HV–240,
SIRIUS D4)
1. Connect the test equipment as described in the
Scan Tool Equipment Manual.
2. If communication between the scan tool and the
test equipment was unsuccessful, wait 30 seconds
and try again.
3. If communication was not successful on the second
try, turn the ignition OFF and check the wire and
connectors between the immobilizer control unit
terminal 7 and the data link connector (DLC) termi-
nal 7.
4. If the wire and connectors between the DLC and
the immobilizer control unit are okay, replace the
immobilizer control unit. Refer to ”Immobilizer Con-
trol Unit” in this section.