2004 DAEWOO LACETTI speed sensor

AISIN AUTOMATIC TRANSAXLE 5A2 – 107
DAEWOO V–121 BL4
Installation Procedure
Notice : Lubricate the O–ring with ISU DEXRON III.
1. Install a new O–ring on the ISS sensor.
2. Install the ISS sensor and retaining bolt into the
transaxle case.
Tighten
Tighten the ISS sensor retaining bolt to 5.4 NSm (48
Ib–in).
3. Connect the ISS sensor electrical connector.
4. Connect the negative battery cable.
OUTPUT SHAFT SPEED (OSS)
SENSOR
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the output shaft speed (OSS) sensor
electrical connector.
3. Remove the OSS sensor retaining bolt.
4. Remove the OSS sensor from the transaxle.

5A2 – 108IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
Installation Procedure
Notice : Lubricate the O–ring with ISU DEXRON III.
1. Install a new O–ring on the output shaft speed
(OSS) sensor.
2. Install the OSS sensor and retaining bolt into the
transaxle.
Tighten
Tighten the OSS sensor retaining bolt to 7.4 NSm (65
Ib–in).
3. Connect the OSS sensor electrical connector.
4. Connect the negative battery cable.
TRANSMISSION CONTROL MODULE
(TCM)
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the transmission control module (TCM)
electrical connector.
3. Remove the TCM retaining bolts.
4. Remove the TCM.

5A2 – 112IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
7. Disconnect the input shaft speed (ISS) sensor elec-
trical connector.
8. Disconnect the output shaft speed (OSS) sensor
electrical connector.
9. Disconnect the Transmission Range (TR) Switch
electrical connector.
10. Disconnect the transaxle electrical connector.
11. Remove the service hall cover.
12. Remove the three torque converter bolts.
13. Remove the damping block connection nut and
bolt.
14. Remove the rear mounting bracket bolts and rear
mounting bracket.
15. Remove the three upper transaxle mounting brack-
et bolts.

5A2 – 118IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
8. Remove the screw plug from the transaxle case.
9. Remove the O–ring from the screw plug.
10. Remove the bolt and the input shaft speed (ISS)
sensor.
11. Remove the breather plug.
12. Remove the O–ring from the breather plug.
13. Remove the bolt and the output shaft speed (OSS)
sensor.
14. Remove the 18 bolts.
15. Remove the oil pan and gasket.
16. Remove the drain plug from the oil pan.

AISIN AUTOMATIC TRANSAXLE 5A2 – 163
DAEWOO V–121 BL4
120. Install the oil strainer to the valve body with the
3 bolts.
Tighten
Tighten the bolts to 9.8 NSm (87 lb–in).
121. Install the 2 magnets in the oil pan.
122. Install a new gasket to the oil pan and install
them to the transaxle case with the 18 bolts.
Tighten
Tighten the bolts to 7 NSm (62 lb–in).
123. Install the output shaft speed (OSS) sensor.
Tighten
Tighten the bolt to 7.4 NSm (65 lb–in).

5A2 – 164IAISIN AUTOMATIC TRANSAXLE
DAEWOO V–121 BL4
124. Install the No.1 breather plug.
125. Install the input shaft speed (ISS) sensor with
the bolt.
Tighten
Tighten the bolts to 5.4 NSm (48 lb–in).
126. Coat a new O–ring with ATF, install it to the
screw plug.
127. Install the screw plug to the transaxle case.
Tighten
Tighten the bolts to 7.4 NSm (65 lb–in).
128. Coat new 2 O–rings with ATF, install them to
the unions.
129. Install the 2 unions to the transaxle case.
Tighten
Tighten the unions to 25 NSm (18 lb–ft).
130. Install the TR switch onto the manual valve
lever shaft and temporarily install the 2 adjusting
bolts.
131. Install a new lock washer and nuts.
Tighten
Tighten the nuts to 12 NSm (106 lb–in).

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.

AISIN AUTOMATIC TRANSAXLE 5A2 – 219
DAEWOO V–121 BL4
Timing Solenoid
Timing solenoid is installed directly in the valve body. The
solenoid operates of ON/OFF by the control signal from
TCM. The solenoid change timing valve of inside the valve
body, operate hydraulic control with apply and drain of for-
ward clutch.
Lock–Up Solenoid
Lock–up solenoid is installed in the valve body. It recieves
control signal from TCM.
Lock–up solenoid operates the lock–up valve inside the
valve body and controls the torque converter lockup func-
tion.
Pressure Control Solenoid (PCS)
The pressure control solenoid (PCS) is located inside the
valve body and regulates the transmission’s fluid pressure
system. It is internally grounded in the TCM and operates
when it is supplied with battery voltage from the TCM,
through the PCS and back to the TCM.
The battery voltage is controlled by a varying current from
the TCM.
The strength of the current is a function of the throttle posi-
tion.
Transmission Fluid Temperature (TFT)
Sensor
TFT sensor provides TCM with information on the trans-
mission fluid temperature.
The TCM uses information from the TFT sensor to calcu-
late the gear shift points and to engage the torque convert-
er lockup function.
Input Shaft Speed (ISS) Sensor
ISS sensor is located on the upper position of the transaxle
and detects A/T input speed from the rotation number of
the direct clutch drum.
They transmit to TCM as a signal.