Mitsubishi Eclipse. Technical Information Manual (1994) - part 44

POWER TRAIN 

 Automatic Transaxle

Reverse

With the manual valve moved to the reverse position,
line pressure is allowed through the manual valve
directly to the reverse clutch and also through the

 solenoid to the low/reverse clutch. The regu-

lator valve is designed to increase line pressure
in the reverse gear range above the pressure that
is normal for other ranges. This is done to increase

clutch capacity. Line pressure is directed between
a small valve and larger valve at the right end of

the regulator valve. This neutralizes the effects of
the larger valve on the regulator valve. With only 
the smaller valve working against the regulator
valve, the regulator valve spring further closes down
the vent, causing line pressure to increase. There
are no solenoids energized in the reverse gear
range. However, the 

 solenoid is modulated

during initial engagement to smooththe torque tran-
sition and prevent harsh engagement into reverse.

REVERSE

REVERSE

 

 

 

 

 

 

 

 

 

   

   

 

 

LR   Low reverse
UD   Underdrive

   Reverse

AC   Accumulator

PT   Pressure tap

   Solenoid

24   2-4 clutch
OD   Overdrive
SW   Switch
CC   Converter CL
D   Dribbler
V   Vent

 

POWER TRAIN 

 Automatic Transaxle

Reverse Block Above Eight MPH
Reverse gear will not engage if the TCM senses

vehicle speed above eight mph. This is to prevent
damage that could occur if a driver accidentally

puts the gear selector in 

 while rolling in any

forward gear range. If the output speed sensor de-
tects that the output shaft is spinning at a speed
equal to or greater than eight mph, the TCM activates

reverse block to protect the transaxle. The function

REVERSE BLOCK

Shift to Rev. w/speed over 8 mph

REVERSE BLOCK

SHIFT TO REV. Y/SPEED OVER 8 MPH

 

 

 

is inoperable in “limp-in” mode. To accomplish or
initiate reverse block, the TCM energizes the 
solenoid. The solenoid prevents line pressure from
applying the low/reverse clutch. Without a holding
element, the planetary 

 in this range will

provide no output. It must have both an input and
a holding element to provide output. In this condition,

the transaxle is effectively in Neutral.

LR   Low reverse
UD   Underdrive

   Reverse

AC   Accumulator
PT   Pressure tap
S   Solenoid

24   2-4 clutch
OD   Overdrive
SW   Switch
CC   Converter CL

D   Dribbler

V   Vent

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

POWER TRAIN 

 Automatic Transaxle

First Gear

When any of the forward gear selections are made,
line pressure is directed to all four solenoids. In
first gear the TCM will energize the 

 and

 solenoids. This action applies the 

verse and underdrive clutches. The forward gear
position selected by the driver has no effect on
manual valve position. Its location will be the same

for all forward positions. The selection difference
is detected by the TCM through the transmission
range and park/neutral position switches. The
switches provide the TCM with the information 
ed to determine which shift pattern and schedule

to use for the selected gear range.

FIRST GEAR

LR   Low reverse
UD   Underdrive

   Reverse

AC   Accumulator

PT   Pressure tap

S   Solenoid

24   2-4 clutch
OD   Overdrive

SW   Switch
CC   Converter CL

D   Dribbler

V   Vent

FIRST GEAR

 

 

 

 

 

 

 

 

 

 

 

 

     

 

 

 

II II

 

POWER TRAIN 

 Automatic Transaxle

Second Gear

There are no solenoids energized in second gear.

clutch engagement. When the TCM recognizes a

With the solenoids de-energized, line pressure is

problem or is unable to function properly, the 

directed to the 2-4 and underdrive clutches. Line

axle goes into a default or limp-in mode. In this

pressure from the 2-4 clutch circuit is also directed

mode of operation, the solenoids and valve body

to the solenoid switch valve, which moves the valve

shift to a position that only provides second gear

to the left. When the solenoid switch valve is moved

range, regardless of any forward gear that is 

to this position, it opens a circuit that can be applied

 by the driver.

by the TCM and LWCC solenoid for torque converter

SECOND GEAR

LR   Low reverse
UD   Underdrive

   Reverse

AC   Accumulator

PT   Pressure tap
S   Solenoid

24   2-4 clutch
OD   Overdrive
SW   Switch
CC   Converter CL
D   Dribbler
V   Vent

SECOND GEAR

 

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