Page 3017 of 5127
Operations of Clutches and Brakes
Fig. 449: Operations Of Clutches And Brakes
Courtesy of GENERAL MOTORS CORP.
Operations of Clutches and Brakes
counterclockwise.
21st and Reverse BrakePrevents the planetary carrier from turning
either clockwise or counterclockwise.
8No. 1 One-Way ClutchWhen 4 is operating, this clutch prevents rear
sun gear from turning counterclockwise.
1No. 2 One-Way ClutchPrevents the planetary carrier from turning
counterclockwise.
Planetary Gear
These gears change the route through which
driving force is transmitted, in accordance
with the operation of each clutch and brake, in
order to increase or reduce the input and
output speed.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 468 © 2005 Mitchell Repair Information Company, LLC.
Page 3018 of 5127

Transmission Range Reference
Clutch and BrakeOperation
C1Forward Clutch
Connects the intermediate shaft and the front
sun gear.
C2Direct ClutchConnects the input shaft and the planetary
carrier.
C3Reverse ClutchConnects the intermediate shaft and the rear
sun gear.
B1O/D and 2nd BrakeLock rear sun gear
B22nd BrakeLock rear sun gear
B31st and Reverse BrakeLock planetary carrier
F11-Way Clutch No. 1Lock counterclockwise rotation of the rear sun
gear, when B2 operations
F21-Way Clutch No. 2Lock counterclockwise rotation of the
planetary carrier
PositionSolenoidClutchBrakeOne-Way
Clutch
Shift 1Shift 2TimingC1C2C3B1B2B3F1F2
PONONOFFOFFOFFOFFOFFOFFOFFOFFOFF
R
V less
than 9
km/h (5
mph)
ONONOFFOFFOFFONOFFOFFONOFFOFF
V
greater
than or
equal to
9 km/h
(5 mph)
ONONONOFFOFFOFFOFFOFFOFFOFFOFF
NONONOFFOFFOFFOFFOFFOFFOFFOFFOFF
D
1stONONOFFONOFFOFFOFFOFFOFFOFFON
2ndONOFFOFFONOFFOFFOFFONOFFONOFF
3rdOFFOFFOFFONONOFFOFFONOFFOFFOFF
3-4OFFONON-
OFFON-
OFFONOFFOFF-
ONONOFFOFFOFF
4thOFFONOFFOFFONOFFONONOFFOFFOFF
2
1stONONOFFONOFFOFFOFFOFFOFFOFFON
2ndONOFFOFFONOFFOFFONONOFFONOFF
3rdOFFOFFOFFONONOFFOFFONOFFOFFOFF
11stONONOFFONOFFOFFOFFOFFONOFFON
2ndONOFFOFFONOFFOFFONONOFFONOFF
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 469 © 2005 Mitchell Repair Information Company, LLC.
Page 3019 of 5127

ELECTRONIC COMPONENT DESCRIPTION
Transmission Control Module (TCM)
The transmission control module (TCM) primarily controls shift points and lockup engagement. It is located on
the driver side under the instrument panel.
The transmission is controlled by an electronic shift system. The TCM processes input signals. From the
information received, the TCM controls the transmission hydraulic system.
The electronic shift system consists of the following components.
TCM
Shift solenoids (SS1 and SS2)
Pressure control solenoid (PCS)
Lockup solenoid
Input shaft speed (ISS) sensor
Output shaft speed (OSS) sensor
Transmission fluid temperature (TFT) sensor
Park/neutral position (PNP) switch
Park/Neutral Position (PNP) Switch
The PNP switch transmits the information which range includes the shift lever of the automatic transmission
(A/T) to the starter and TCM.
It is possible for the PNP switch to start an engine in only park (P) and neutral (N) prevention of reckless
driving
The PNP switch makes the backup lamp turn on when reversing.
It is used for PNP switch to shift control.
The PNP switch transmits the information by combination of starter and reverse circuit to the vehicle side
directl
y without TCM.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 470 © 2005 Mitchell Repair Information Company, LLC.
Page 3020 of 5127
Fig. 450: PNP Switch Chart
Courtesy of GENERAL MOTORS CORP.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 471 © 2005 Mitchell Repair Information Company, LLC.
Page 3021 of 5127
Fig. 451: PNP Switch, Nut, Washer & Control Lever
Courtesy of GENERAL MOTORS CORP.
Shift Solenoid No 1, 2 (SS1, SS2)
Two shift solenoids are installed directly in the valve body. The solenoids operate of ON and OFF by the
control si
gnal from TCM. Combinations of 2 solenoids, SS1 (2) and SS2 (1) changes gear ranges.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 472 © 2005 Mitchell Repair Information Company, LLC.
Page 3022 of 5127
Fig. 452: Shift Solenoid No 1, 2 (SS1, SS2)
Courtesy of GENERAL MOTORS CORP.
Timing Solenoid
The timing solenoid (1) 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
appl
y and drain of forward clutch.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 473 © 2005 Mitchell Repair Information Company, LLC.
Page 3023 of 5127
Fig. 453: Timing Solenoid
Courtesy of GENERAL MOTORS CORP.
Lock-Up Solenoid
The lock-up solenoid (1) is installed in the valve body. It receives control signal from TCM.
The lock-up solenoid operates the lock-up valve inside the valve body and controls the torque converter lockup
function.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 474 © 2005 Mitchell Repair Information Company, LLC.
Page 3024 of 5127
Fig. 454: Lock-Up Solenoid
Courtesy of GENERAL MOTORS CORP.
Pressure Control Solenoid (PCS)
The PCS (1) 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 position.
2006 Chevrolet Aveo
2006 TRANSMISSION Automatic Transaxle - Aisin (81-40LE) - Introduction (2 Of 2) - Aveo
Microsoft
Thursday, July 16, 2009 1:17:34 PMPage 475 © 2005 Mitchell Repair Information Company, LLC.