2004 DAEWOO LACETTI Reverse switch

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.

5A2 – 2IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Shift Control Lever Assembly 5A2–100. . . . . . . . . . . . .
Transmission Range (TR) Switch 5A2–101. . . . . . . . .
Shift Control Cable 5A2–104. . . . . . . . . . . . . . . . . . . . . .
Shift Select Cover 5A2–105. . . . . . . . . . . . . . . . . . . . . .
Input Shaft Speed (ISS) Sensor 5A2–106. . . . . . . . . .
Output Shaft Speed (OSS) Sensor 5A2–107. . . . . . . .
Transmission Control Module (TCM) 5A2–108. . . . . .
Fluid Cooler Inlet Pipes and Hoses 5A2–109. . . . . . . .
Fluid Cooler Outlet Pipes and Hoses 5A2–110. . . . . .
Transaxle Assembly 5A2–111. . . . . . . . . . . . . . . . . . . . .
UNIT REPAIR 5A2–117. . . . . . . . . . . . . . . . . . . . . . . . . . .
Major Component Disassembly 5A2–117. . . . . . . . . . .
Major Component Assembly 5A2–137. . . . . . . . . . . . .
Oil Pump 5A2–167. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Direct Clutch 5A2–171. . . . . . . . . . . . . . . . . . . . . . . . . . .
Planetary Ring Gear 5A2–178. . . . . . . . . . . . . . . . . . . .
One–Way Clutch 5A2–180. . . . . . . . . . . . . . . . . . . . . . .
Forward and Reverse Clutch 5A2–183. . . . . . . . . . . . .
Counter Driven Gear 5A2–192. . . . . . . . . . . . . . . . . . . .
Valve Body 5A2–195. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differential Case 5A2–208. . . . . . . . . . . . . . . . . . . . . . . .
GENERAL DESCRIPTION AND SYSTEM
OPERATION5A2–218 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transaxle Description 5A2–218. . . . . . . . . . . . . . . . . . .
Electronical Components 5A2–218. . . . . . . . . . . . . . . .
Hydraulic Control System 5A2–221. . . . . . . . . . . . . . . .
Automatic Transaxle System 5A2–222. . . . . . . . . . . . .

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.)

AISIN AUTOMATIC TRANSAXLE 5A2 – 47
DAEWOO V–121 BL4
DIAGNOSTIC TROUBLE CODE (DTC) P0705
TRANSMISSION RANGE (TR) SWITCH CIRCUIT
MALFUNCTION
Conditions for Setting the DTC
S TCM detects more than two equal signals from the
Park/Neutral Position switch circuit for 10 seconds
continuously.
S TCM detects the no signal of TR switch circuit for 2
seconds continuously.
S Vehicle speed is 30 km/h (19 mph) or greater.
S Engine revolution is 1500 rpm or greater.
Action Taken When the DTC Sets
S TCM will request the illumination of MIL and store
DTC when TCM detects failures on two consecu-
tive ignition cycle.
S TCM judges with the priority. (D>2>1>R>N>P)
S No timing solenoid control for N–D
S No self–learning control
S No lockupS No prevent reverse gear control
Conditions for Clearing the DTC
S The TCM turns off the MIL when no further failures
detected for three consecutive ignition cycles.
S The scan tool can clear the DTC from the TCM his-
tory.
S The TCM clears the DTC from the TCM history
memory after forty consecutive warm up cycles
without fault.
S TCM detects single ”D range” signal of the TR
switch.
Cause of Failure
S Wiring harness or connector between TR switch
and TCM
S TR switch
S TCM

AISIN AUTOMATIC TRANSAXLE 5A2 – 117
DAEWOO V–121 BL4
UNIT REPAIR
MAJOR COMPONENT DISASSEMBLY
Tools Required
DW240–020 Brake/Clutch Spring Compressor
DW240–050 Overdrive Brake Adapter
DW240–060–01 Brake Spring Compressor Bolt/Nut
DW240–070 1st & Reverse Brake Adapter
DW240–080 2nd Brake Adapter
DW240–090 Planetary Ring Gear Remover
DW240–150 Transaxle Case Side Bearing Outer Race
Adapter
DW240–170 Adapter Handle
DW260–021–02 Automatic Transaxle Overhaul Fixture
(81–40 LE)
DW260–041 Planetary Ring Gear Nut Removal/Installa-
tion Socket
Disassembly Procedure
1. Remove the transaxle assembly from the vehicle.
Refer to”Transaxle Assembly” in this section.
2. Install the transaxle assembly to the transaxle sup-
port stand using Automatic Transaxle Overhaul Fix-
ture DW260–021–02 (81–40 LE).
3. Remove the nut, washer and control lever.
4. Using a screwdriver, unstake the lock washer.
5. Remove the two bolts and nut and pull out the
transmission range (TR) switch.
6. Remove the two unions the transaxle case.
7. Remove the two O–rings from the unions.

5A2 – 218IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
TRANSAXLE DESCRIPTION
The new automatic transmission is an electronically con-
trolled 4–speed automatic transmission with Lock–up
mechanism.
The transmission is mainly composed of the torque con-
verter with lock up clutch, newly developed 4–speed plan-
etary gear unit, the hydraulic control system and the elec-
tric control system.
ELECTRONICAL COMPONENTS
Transmission Control Module (TCM)
The TCM primarily controls shift points and lockup en-
gagement. It is located on the driver side under the instru-
ment panel.
The transmission is controlled by an electronic shift sys-
tem. The Transmission Control Module (TCM) processes
input signals. From the information received, the TCM
controls the transmission hydraulic system.
The electronic shift system consists of the following :
S Transmission control module (TCM)
S Shift solenoids (SS1 and SS2)
S Pressure control solenoid (PCS)
S Lockup solenoid
S Input shaft speed (ISS) sensor
S Output shaft speed (OSS) sensor
S Transmission Fluid Temperature (TFT) sensor
S Transmission Range (TR) Switch
Transmission Range (TR) Switch
Transmission Range (TR) Switch transmits the informa-
tion which range includes shift lever of A/T to Starter and
TCM.
S It is possible for TR switch to start an engine in only
”P” and ”N”. (Prevention of reckless driving)
S TR switch makes backup lamp turn on when re-
versing.
S It is used for TR switch to shift control.
TR switch transmits the information by combination of
starter and reverse circuit to vehicle side directly without
TCM.
Shift Solenoid No 1,2 (SS1, SS2)
2 shift solenoids are installed directly in the valve body.
The solenoids operate of ON and OFF by the control sig-
nal from TCM. Combinations of 2 solenoids, SS1 and SS2
changes gear ranges.

FIVE–SPEED MANUAL TRANSAXLE 5B – 7
DAEWOO V–121 BL4
Checks Action
Check for a noise in the fourth gear (4) only.S Replace any chipped, scored, or worn fourth gear or
output gear.
S Replace any worn third–fourth gear synchronizer.
S Replace any worn fourth–gear/bearing.
S Replace any worn differential–gear/bearing.
S Replace any worn–ring gear.
S Adjust, repair, or replace the shift lever and the rods.
Check for a noise in the fifth gear (5) only.S Replace any chipped, scored, or worn fifth gear or
output gear.
S Repair any worn fifth–gear synchronizer.
S Replace any worn fifth–gear/bearing.
S Replace any worn differential–gear/bearing.
S Replace any worn–ring gear.
S Adjust, repair, or replace the shift lever and the rods.
Check for a noise in the reverse (R) gear only.S Replace any chipped, scored, or worn reverse idler
gear, idler–gear bushing, input gear, or output gear.
S Replace any worn first–second gear synchronizer.
S Replace any worn output gear.
S Replace any worn differential–gear/bearing.
S Replace any worn–ring gear.
Check for a noise in all gears.S Add sufficient lubricant.
S Replace any worn bearings.
S Replace any chipped, scored, or worn input–gear
shaft or output–gear shaft.
Check for the transaxle slipping out of gear.S Adjust or replace the linkage, as needed.
S Adjust, repair, or replace any binding shift linkage.
S Tighten or replace the input–gear bearing retainer, as
needed.
S Repair or replace any worn or bent shift fork.
Check for a leak in the area of the clutch.S Repair the transaxle casing.
S Replace any damaged release bearing guide.
Check for a leak at the center of the transaxle.S Repair the transaxle casing.
S Repair the shift mechanism.
S Replace the damaged backup lamp switch.
Check for a leak at the differential.S Adjust or replace the bearing retainers.
S Tighten or replace the differential cover.
S Adjust or replace the drive axle shaft seals.

5B – 14IFIVE–SPEED MANUAL TRANSAXLE
DAEWOO V–121 BL4
1. Gear Shift Control
2. Bolt
3. Gear Shift Tube Bellows
4. Clamp
5. Bolt
6. Gear Shift Control Mode
7. Gear Shift Guide Control
8. Pin
9. Clip
10. Bolt
11. 1st & 2nd Gear Shift Fork
12. 1st & 2nd Gear Shift Rod
13. Pin
14. 3rd & 4th Gear Shift Fork
15. 3rd & 4th Gear Shift Rod
16. Pin
17. 5th Speed Engaging Piece
18. Gear Shift Rod Pawl
19. Reverse Gear Shift Fork
20. Reverse Gear Shift Rod
21. Pin
22. Gear Shift Rod
23. Shift Finger24. Gear Shift Lever Cover
25. Gear Shift Inter Lever
26. Plate
27. Compression Spring
28. Bush
29. Retaining Ring
30. Gear Shift Cover Gasket
31. Bolt
32. Plug
33. Plug
34. Speedometer Driven Gear
35. Bolt
36. Differential Gear Cover Gasket
37. Differential Gear Cover
38. Screw
39. Backup Lamp Switch
40. O–ring
41. Pin
42. Pin
43. Sleeve
44. Bush