2004 DAEWOO LACETTI light

5A1 – 184IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P1884
4–3 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
– The transaxle can be of more compact design
and is lighter on account of the absence of free-
wheels and the lower number of shift elements.– Lower drag losses, i.e. higher efficiency.
– Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting the DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not in N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

5A1 – 186IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P1885
3–1 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
– The transaxle can be of more compact design
and is lighter on account of the absence of free-
wheels and the lower number of shift elements.– Lower drag losses, i.e. higher efficiency.
– Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting the DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not in N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

5A1 – 188IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
RangePark/
Neutr
alRever
seD321
GearNR1st2nd3rd4th1st2nd3rd1st2nd1st
Solenoid Valve
1ONON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFFON/
OFF
Solenoid Valve
2ONONONOFFOFFOFFONOFFOFFONOFFON
Line Pressure
Control Sole-
noid Valve 3
(EDS 3)OFFOFFOFFONON/
OFFON/
OFFOFFONON/
OFFOFFONOFF
Line Pressure
Control Sole-
noid Valve 4
(EDS 4)ONOFFONONONOFFONONONONONON
Line Pressure
Control Sole-
noid Valve 5
(EDS 5)OFFOFFONONOFFOFFONONOFFONONON
Line Pressure
Control Sole-
noid Valve 6
(EDS 6)ONOFFONONONOFFONONONONONON
Brake BAAAAAAAA
Brake CH
Brake DH
Clutch EAAAAAA
Brake FHHHHHHH
Lock–up
ClutchA
A = Applied
H = Holding
ON = The solenoid is energized.
OFF = The solenoid is de–energized.
** = Manual Second–Third gear is only available above approximately 100 km/h (62 mph).
*** = Manual First–Second gear is only available above approximately 60 km/h (37 mph).
Note : Manual First–Third gear is also possible at high vehicle speed as a safety feature.
DIAGNOSTIC TROUBLE CODE(DTC) P1886
4–2 SHIFT MALFUNCTION
Circuit Description
The special feature of 4HP 16 Auto Transaxle is that it op-
erates without freewheels. Shifting between individual
gears takes place by means of overlapping clutch engage-
ment and release.
The advantage of overlap shifting are as follows:
– The transaxle can be of more compact design
and is lighter on account of the absence of free-
wheels and the lower number of shift elements.– Lower drag losses, i.e. higher efficiency.
– Lower peak torque acting on the components and
driveline.
However, overlap shifting necessitates high–performance
hardware and software, and precision engine signals.
Conditions for Setting the DTC
S Transmission oil temperature is greater than –10°C
(14°F).
S Selector lever is not in N(Neutral), P(Park) position.
S System voltage is greater than 9 volts.

ZF 4 HP 16 AUTOMATIC TRANSAXLE 5A1 – 227
DAEWOO V–121 BL4
2. Find the disc set’s thickness. Refer to the below
table.
PF
Disc set’s Thickness
3.01~3.19mm1.8mm
3.20~3.48mm2.1mm
3.49~3.88mm2.5mm
3.89~4.08mm2.7mm
4.09~4.30mm3.0mm
PE is 4.20mm so, the disc set’s thickness is
3.0mm.
3. Replace clutch B’s setting disc. (3.0mm)
TORQUE CONVERTER HOUSING
Disassembly and Assembly Procedure
1. Remove the torque converter bolts.
2. Hit the torque converter housing lightly.
3. Remove the torque converter housing.
Installation Notice
S First pre–tighten the bolts in the following or-
der.(7,20)(12,23)(16,4)
Tighten
Tighten the bolts to 15 NSm (11 lb–ft).
S Then, tighten the bolts in the following order. (15,3)
(16,4) (14,5) (13,23) (12,22)(11,21)
(10,20) (9,19) (8,18) (7,17) (6) (1,2)
S Last, in numerical order, tighten the bolts all the
way.(123)
Tighten
Tighten the bolts to 23 NSm (17 lb–ft).
4. Take out the metal gasket.
5. Take out the paper gasket.
6. Remove the oil filter bolt and oil filter.
Installation Notice
Tighten
Tighten the oil filter bolt to 10 NSm (89 lb–in).

5A1 – 232IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
The ZF 4HP 16 automatic transaxle consists primarily of
the following components.
Mechanical
S Torque converter with TCC
S Drive link assembly
S Two multiple disk clutch assemblies : Clutch B,E
S Three multiple brake assemblies : Brake C,D,F
S Lock–up clutch valve
S Two planetary gear sets
S One oil pump
S Final drive and differential assembly
Electronic
S Two shift solenoid valve(sol.1,2)
S Four pressure control solenoid valve(EDS)
S Two speed sensors : A/T ISS and A/T OSS
S Fluid temperature sensor
S Automatic transaxle control module(TCM)
S Wiring harness assembly
MECHANICAL COMPONENTS
Torque Converter
The converter consists of the impeller, the turbine wheel,
the reaction member (stator) and the oil to transmit torque.
The impeller, which is driven by the engine, causes the oil
in the converter to flow in a circular pattern. This oil flow
meets the turbine wheel, where is direction of flow is de-
flected. At the hub, the oil leaves the turbine and reaches
the reaction member (stator), where it is once again de-
flected so that it reaches the impeller at the correct angle
of flow.
The reversal effect generates movement in the stator, the
reaction torque then amplifies the turbine torque.
The ratio between turbine torque and torque is referred to
as torque multiplication.
The greater the difference is speed between the pump and
turbine, the greater the torque multiplication; it is at its
highest when the turbine is at a standstill. The higher the
speed of the turbine, the lower the torque multiplication.
When the turbine speed reaches about 85%of the pump
speed, torque multiplication=1, i.e. the turbine torque
equivalent to pump torque.
The stator, which bears against the housing via the free-
wheel, is then rotating freely in the oil flow and the free-
wheel is over–come. From this point onwards, the con-
verter acts as a straightforward fluid coupling.
Space Behind Lock–up Clutch Piston
1. Friction lining
2. Lock–up clutch piston
3. Converter cover
4. Turbine wheel
5. Impeller
6. Stator
7. Turbine hub
8. Torque converter impeller hub
Torque Converter Lock–up Clutch (TCC)
The converter lock–up clutch is a device, which eliminates
converter slip and thus helps to improve fuel consumption.
The previous control principle for converter lock–up clutch
operation has been replaced by a controlling function on
the 4 HP 16. The converter lock–up clutch is engaged and
released in a controlled manner. During the controlled
phase, a slight speed difference between the impeller and
turbine wheel is established. This ensures that the en-
gine’s rotating vibration is not phased on to the transaxle.
The result is optimum shift quality.
An electronic pressure–regulating valve determines pres-
sure regulation of the lock–up converter clutch’s piston.
When open (conversion range), the oil pressure behind
the converter lock–up clutch piston and in the turbine zone
is equal. The direction of flow is through the turbine shaft
and through the space behind the piston, to the turbine
chamber.

5A1 – 236IZF 4 HP 16 AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
ELECTRONICAL COMPONENTS
Selector Lever/Program Switch
The driver engages the travel position via the selector le-
ver:
P : Park Position
R : Reverse
N : Neutral
D : Forward Speeds
Park/Neutral Position Switch
The Park/Neutral Position Switch is located on the selec-
tor shaft and informs the TCM of the current selector lever
position P–R–N–D–3–2–1.
The selector lever position is transmitted to the TCM in en-
coded form along 4 lines. The encoding is such that mal-
functions in the connecting lead are identified.
The Park/Neutral Position Switch is located on the selec-
tor shaft, which is connected to the selector lever via a pull
cable. In addition, the Park/Neutral Position Switch con-
trols the starter interlock, the reversing light and the selec-
tor lever position indicator on the instrument panel.
Signal Combination
L1L2L3L4
P00120
R00012
N01200
D1212120
31212012
21201212
10121212
Automatic Transaxle Output Speed Sensor
(A/T OSS)
The vehicle A/T OSS is a magnetic inductive pickup that
relays information relative to vehicle speed to the TCM.
Vehicle speed information is used by the TCM to control
shift timing, line pressure, and TCC (lock–up clutch) apply
and release.
The output speed sensor mounts in the case at the speed
sensor rotor, which is pressed onto the spur gear. An air
gap of 0.1mm~1.3mm(0.004~0.05in) is maintained be-
tween the sensor and the teeth on the spur gear teeth. The
sensor consists of a permanent magnet surrounded by a
coil of wire.
As the differential rotates, an AC signal is generated by the
output speed sensor (OSS).
Automatic Transaxle Input Speed Sensor
(A/T ISS)
The A/T ISS is a magnetic inductive pickup that relays in-
formation relative to transaxle input speed to the TCM.
The TCM uses transaxle input speed information to con-
trol line pressure, TCC apply and release and transaxle
shift patterns. This information is also uses to calculate the
appropriate operating gear ratios and TCC slippage.
The input speed sensor mounts onto piston B that is inside
of valve body.
An air gap of 1.8~2.2mm(0.07~0.086inch) is maintained
between the sensor and the piston B.
The sensor consists of a permanent magnet surrounded
by a coil of wire. As the piston B is driven by the turbine
shaft, an AC signal induced in the input speed sensor.
Higher vehicle speeds induce a higher frequency and volt-
age measurement at the sensor.
Sensor resistance should measure between 825~835
ohms at 20°C (68°F). Sensor can measure from
1,000~8,000HZ.

AISIN AUTOMATIC TRANSAXLE 5A2 – 27
DAEWOO V–121 BL4
WIRING HARNESS AND
CONNECTOR INSPECTION
1. Reproducing test
Perform symptom simulation test on the basis of
user’s condition. Refer to the below factors.
S Occuring–road condition, speed, accelerate,
reduce speed, straight, curve, air temperature,
weather, etc.
2. Inspect the connection condition of between con-
nectors.
Inspect the failure between connectors by visual
check and contact pressure check.
S Connector disconnected
S Terminals rusted
S Terminals deformation or loose fit
3. Inspect the Continuity of the wiring harness.
Disconnect both ends connector of wiring har-
ness, measure resistance between one connec-
tor terminal and other.
S Normal : 1Ω or less (No open circuit)
S Abnormal :
Ω (Open circuit)
Notice : Measure the resistance while slightly shaking
wire harness vertically and horizontally.
It is rare case wiring harness is broken at the middle of it,
and most cases occur at the connector.
4. Inspect the short circuit of the wiring harness.
Disconnect the connectors of the wiring harness
at both ends, measure resistance between the
applicable terminals of the connector and body
earth.
S Normal : 1M Ω or higher (No short circuit)
S Abnormal : Low resistance (Short circuit)Measure the resistance between one terminal
an another terminal in the same connector.(Ex-
cept between power supply or between earth).
S Normal : 1M Ω or higher (No short circuit)
S Abnormal : Low resistance (Short circuit)
Notice : Measure the wiring harness while slightly shaking
vertically and horzontally.
It is usual case of the short circuit that wiring harness is
crowded body and clamping failure.
5. Temporary connection failure of the connector.
It is thought that temporally the connection fail-
ure of the connector is cause when you can not
decide cause of DTC detection.
Therfore make sure to inspect and clean the
connector and delete the memorized DTC.
ROAD TEST
Road test is to diagnosis failure symptom accurately and
check the failure symptom after procedure.
Confirm whether below condition before road test. Oil tem-
perature is hot condition (50°C (122°F) ~ 80°C (176°F)).
1. D range test
S Check for up–shift, down–shift, kick–down and
lock–up operation at the shift point shown in the
shift schedule.
S Check for engine brake operation.
S Check for Check abnormal shock, noise and
harshness.
2. ”P” range test
Park vehicle on a gradient (more than 5°), shift
into the ”P” range and release parking brake.
Then, check to see no moving vehicle by opera-
tion of parking lock pawl.

5A2 – 28IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
FUNCTION CHECK
Confirm whether below condition before function check.
S Oil temperature is hot condition (50°C (122°F) ~
80°C (176°F)).
S Switch of A/C and light etc are off.
Stall Test
Stall test’ purpose is to inspect overall performance of A/T
and engine by measuring the stall speed in ”D” and ”R”
range.1. Chock 4 Wheels and apply parking brake fully, lock
vehicle perfectly.
2. Fully pressed on foot brake pedal with left foot.
3. Shift into ”D” and ”R” range, fully press on accelera-
tor pedal with right foot.
Quickly read stall speed at this time.
Standards
2390 ± 150 rpm
Notice : Do not continuously run longer than 5 sec be-
cause of extreme increasing oil temp.
Make sure to keep interval for more than 1 min between
stall tests.
Result of Stall Test
Cause of Failure
Lower than standards
both ”D” and ”R”Less engine power
Torque converter one way clutch failure
Higher than standards
only ”D”Lower line pressure
S Pressure control solenoid (PCS) failure
S Primary regulator valve failure
Forward clutch (C1) failure (Slipping)
No.2 One–way clutch (F2) failure
Higher than standards
only ”R”Lower line pressure
S Pressure control solenoid (PCS) failure
S Primary regulator valve failure
Reverse clutch (C3) failure (Slipping)
1st & reverse brake (B3) failure (Slipping)
Higher than standards
both ”D” and ”R”Lower line pressure
S Pressure control solenoid (PCS) failure
S Primary regulator valve failure
Oil pump failure
Oil strainer failure (clogging)
Oil leak for each range circuit
Time Lag Test
Time lag is time till slightly shock can be felt when shift le-
ver is shifted ”N”  ”D” and ”N”  ”R” while engine idling.
Time lag test can inspect hydraulic condition and clutch/
brake condition.
1. Chock 4 Wheels and apply parking brake fully, lock
vehicle perfectly.
2. Measure time lag by using stop watch from moment
when shift lever is shifted in ”N”  ”D” and ”N” 
”R” until moment slightly shock can be felt.”N  D”less than 0.7 sec
”N”  ”R”less than 1.2 sec
Notice : Make sure to take 3 measurement and take the
average value.
Make sure to keep interval for more than 1 min between
time lag tests. (That purpose is to remove clutch/brake
pressure was left unfinished.)