ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 49
DAEWOO V–121 BL4
Functional Check Procedure
Inspect
1. Install a tachometer or scan tool.
2. Operate the vehicle unit proper operating tempera-
ture is reached.
3. Drive the vehicle at 80 to 88km/h (50 to 55 mph)
with light throttle(road load).
4. Maintaining throttle position, lightly touch the brake
pedal and check for release of the TCC and a slight
increase in engine speed(rpm).
5. Release the brake slowly accelerate and check for
a reapply of the Lock up clutch and a slight de-
crease in engine speed(rpm).
Torque Converter Evaluation
Torque Converter Stator
The torque converter stator roller clutch can have one of
two different type malfunctions :
A. Stator assembly freewheels in both directions.
B. Stator assembly remains Locked up at all times.
Condition A – Poor Acceleration Low
Speed
The car tends to have poor acceleration from a stand still.
At speeds above 50 to 55km/h(30 to 35mph), the car may
act normal. If poor acceleration is noted, it should first be
determined that the exhaust system is not blocked, and
the transaxle is in 1st(First) gear when starting out.
If the engine freely accelerates to high rpm in N(Neutral),
it can be assumed that the engine and exhaust system are
normal. Checking for poor performance in ”Drive” and ”Re-
verse” will help determine if the stator is freewheeling at all
times.
Condition B – Poor Acceleration High
Speed
Engine rpm and car speed limited or restricted at high
speeds. Performance when accelerating from a standstill
is normal. Engine may overheat. Visual examination of the
converter may reveal a blue color from overheating.
If the converter has been removed, the stator roller clutch
can be checked by inserting two fingers into the splined in-
ner race of the roller clutch and trying to turn freely clock-
wise, but not turn or be very difficult to turn counter clock-
wise.
Noise
Torque converter whine is usually noticed when the ve-
hicle is stopped and the transaxle is in ”Drive” or ”Re-
verse”. The noise will increase when engine rpm is in-
creased. The noise will stop when the vehicle is moving or
when the torque converter clutch is applied because both
halves of the converter are turning at the same speed.
Perform a stall test to make sure the noise is actually com-
ing from the converter :1. Place foot on brake.
2. Put gear selector in ”Drive”.
3. Depress accelerator to approximately 1200rpm for
no more than six seconds.
Notice : If the accelerator is depressed for more than six
seconds, damage to the transaxle may occur.
A torque converter noise will increase under this load.
Important : This noise should not be confused with pump
whine noise which is usually noticeable in P (Park), N
(Neutral) and all other gear ranges. Pump whine will vary
with pressure ranges.
The torque converter should be replaced under any of the
following conditions:
S External leaks in the hub weld area.
S Converter hub is scored or damaged.
S Converter pilot is broken, damaged or fits poorly
into crankshaft.
S Steel particles are found after flushing the cooler
and cooler lines.
S Pump is damaged or steel particles are found in the
converter.
S Vehicle has TCC shudder and/or no TCC apply.
Replace only after all hydraulic and electrical diag-
noses have been made.(Lock up clutch material
may be glazed.)
S Converter has an imbalance which cannot be cor–
rected. (Refer To Converter Vibration Test Proce-
dure.)
S Converter is contaminated with engine coolant con-
taining antifreeze.
S Internal failure of stator roller clutch.
S Excess end play.
S Heavy clutch debris due to overheating (blue con-
verter).
S Steel particles or clutch lining material found in fluid
filter or on magnet when no internal parts in unit are
worn or damaged(indicates that lining material
came from converter).
The torque converter should not be replace if :
S The oil has an odor, is discolored, and there is no
evidence of metal or clutch facing particles.
S The threads in one or more of the converter bolt
holes are damaged.
–correct with thread insert.
S Transaxle failure did not display evidence of dam-
age or worn internal parts, steel particles or clutch
plate lining material in unit and inside the fluid filter.
S Vehicle has been exposed to high mileage(only).
The exception may be where the Lock up clutch
damper plate lining has seen excess wear by ve-
hicles operated in heavy and/or constant traffic,
such as taxi, delivery or police use.
Lock–Up Clutch Shudder Diagnosis
The key to diagnosing lock–up clutch(TCC) shudder is to
note when it happens and under what conditions.
SECTION : 7A
HEATING AND VENTILATION 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
SPECIFICATIONS7A–1 . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Temperature Specifications 7A–1. . . . . . . . . . .
Fastener Tightening Specifications 7A–1. . . . . . . . . . .
SCHEMATIC AND ROUTING DIAGRAMS7A–3 . . . . .
Non–A/C Diagrams 7A–3. . . . . . . . . . . . . . . . . . . . . . . .
Airflow – Typical 7A–4. . . . . . . . . . . . . . . . . . . . . . . . . . .
Airflow with Rear Heating Duct 7A–5. . . . . . . . . . . . . .
DIAGNOSIS7A–6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HEATER SYSTEM 7A–6. . . . . . . . . . . . . . . . . . . . . . . . . .
Insufficient Heating or Defrosting 7A–6. . . . . . . . . . . . .
Blower Electrical 7A–9. . . . . . . . . . . . . . . . . . . . . . . . . . .
Improper Air delivery or No Mode Shift 7A–11. . . . . .
Too Much Heat 7A–13. . . . . . . . . . . . . . . . . . . . . . . . . . .
Controls 7A–15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Blower Noise 7A–16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . MAINTENANCE AND REPAIR7A–18 . . . . . . . . . . . . . .
ON–VEHICLE SERVICE 7A–18. . . . . . . . . . . . . . . . . . . .
Temperature Cable Adjustment 7A–18. . . . . . . . . . . . .
Temperature Control Cable 7A–18. . . . . . . . . . . . . . . . .
Control Assembly 7A–20. . . . . . . . . . . . . . . . . . . . . . . . .
Control Assembly Knob Lighting 7A–21. . . . . . . . . . . .
Heater/Air Distributor Case Assembly 7A–21. . . . . . .
Blower Motor 7A–23. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
High–Blower Relay 7A–24. . . . . . . . . . . . . . . . . . . . . . . .
Blower Resistor 7A–25. . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Hoses 7A–25. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heater Core 7A–26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION7A–28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heating and Ventilation Systems 7A–28. . . . . . . . . . . .
SPECIFICATIONS
HEATER TEMPERATURE SPECIFICATIONS
Ambient Air TemperatureHeater Outlet Air Temperature
–18°C (0°F)54°C (129°F)
– 4°C (25°F)59°C (138°F)
10°C (50°F)64°C (147°F)
24°C (75°F)68°C (154°F)
FASTENER TIGHTENING SPECIFICATIONS
ApplicationNSmLb–FtLb–In
Blower Motor–to–A/C Assembly Screws1.2–11
Blower Motor Resistor Screws1.2–11
Blower Motor Retaining Screws1.2–11
Controller Retaining Screws2–18
Heater/Air Distributor Case Assembly Screw4–35
7A – 2IHEATING AND VENTILATION SYSTEM
DAEWOO V–121 BL4
Application Lb–InLb–Ft NSm
Heater Core Cover Screws1.2–11
Heater Core Housing–to–Evaporator Housing Screws1.2–11
HEATING AND VENTILATION SYSTEM 7A – 3
DAEWOO V–121 BL4
SCHEMATIC AND ROUTING DIAGRAMS
NON–A/C DIAGRAMS
7A – 4IHEATING AND VENTILATION SYSTEM
DAEWOO V–121 BL4
AIRFLOW – TYPICAL
HEATING AND VENTILATION SYSTEM 7A – 5
DAEWOO V–121 BL4
AIRFLOW WITH REAR HEATING DUCT
(LEFT–HAND DRIVE SHOWN, RIGHT–HAND DRIVE
SIMILAR)
7A – 6IHEATING AND VENTILATION SYSTEM
DAEWOO V–121 BL4
DIAGNOSIS
HEATER SYSTEM
INSUFFICIENT HEATING OR DEFROSTING
CAUTION : The cooling system is pressurized when hot. Injury can result from removing the surge tank cap be-
fore the engine is sufficiently cool.
Step
ActionValue(s)YesNo
1Verify the customer’s complaint.
Are the customer’s concerns verified?–Go to Step 2System OK
2Check the coolant level.
Is the coolant level correct?–Go to Step 4Go to Step 3
3Add coolant as needed.
Is the repair complete?–System OKGo to Step 4
4Check the timing belt for tension or damage.
Are the drive belts OK?–Go to Step 6Go to Step 5
5Correct any problem with the timing belt.
Is the repair complete?–System OKGo to Step 6
6Check the coolant hoses for leaks or kinks.
Are the coolant hoses OK?–Go to Step 8Go to Step 7
7Repair any problem with the coolant hoses.
Is the repair complete?–System OKGo to Step 8
8Check the surge tank cap. Refer to Section 2D, En-
gine Cooling.
Is the surge tank cap OK?–Go to Step 10Go to Step 9
9Repair or replace the surge tank cap as needed.
Is the repair complete?–System OKGo to Step 10
101. Turn the A/C switch OFF on vehicles equipped
with air conditioning (A/C).
2. Set the blower motor switch on maximum
speed.
3. Set the heater control to full hot.
4. Turn the ignition ON.
5. Check for airflow from the vent outlet.
Is there heavy airflow from the heater outlet?–Go to Step 11Go to Step 26
11Check 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 12Go to ”Blower
Electrical
(Manual and
Non–A/C)”
121. Turn the A/C switch OFF.
2. Set the temperature lever to full hot.
3. Set the blower motor switch on maximum
speed.
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 14Go to Step 13
HEATING AND VENTILATION SYSTEM 7A – 7
DAEWOO V–121 BL4
StepNo Yes Value(s) Action
131. Check for the following problems:
S Restriction in the cooling system.
S Failed water pump impeller.
S Faulty thermostat.
2. Make repairs to the cooling system, as needed.
Are the repairs complete?–System OKGo to Step 14
141. Install the surge tank cap.
2. With the ignition ON, allow the engine to warm
up for about 20 minutes. Drive the vehicle at 48
km/h (30 mph).
3. Use a thermometer to measure the ambient air
temperature and the discharge air temperature
at the heater outlet.
Does the heater output meet the minimum values
given?Go to ”Heater
Temperature
Specifications”Go to Step 15Go to Step 16
151. Check the vehicle for cold air leaks at the fol-
lowing locations:
S Dash.
S Heater cases.
S Vents.
2. Check under the seat for obstructions.
3. Repair any leaks or obstructions.
Are the repairs complete?–System OK–
161. Turn the ignition OFF.
2. Turn the temperature control knob to full cold,
then rapidly to full hot.
3. Listen for the sound of the temperature door
slam just before it reaches the end of the travel
range of the control knob.
Does the door slam?–Go to Step 18Go to Step 17
171. Check the following aspects of the temperature
door:
S Travel.
S Cables.
S Linkage.
2. Verify the accuracy of the temperature controls
at full hot.
3. Verify the accuracy of the temperature controls
at full cold.
Is the repair complete?–System OK–
181. Set the temperature control knob to full hot.
2. Start the vehicle.
3. Check the temperature of the heater inlet hose
and the heater outlet hose by feel. The air tem-
perature around the hoses should be at least
29°C (84°F).
Is the heater inlet hose hot and the heater outlet
hose warm?–Go to Step 19Go to Step 22
19Check the thermostat. Refer to 2D, Engine Cooling.
Is the thermostat installed and seated properly?–Go to Step 20Go to Step 21