Shift Control
The PCM determines which gear should be selected by various signals sent from sensors, and actuates the shift control
solenoid valves A and B to control shifting. Also. a Grade Logic Control System has been adopted to control shifting in E
anO E ('gZ - gg), and E ('99 - 00) position while the vehicle is ascending or descending a slope, or reducing speeo.
PositionGearShift Control Solenoid
Valve A
Shift Control Solonoid
Valve B
E, E, Or
E
'I stOFFON
2ndONON
3rdONOFF
E orE4thOFFOFF
a2ndONON
tr1stOFFON
E-ReverseONOFF
*See page 14-37 for reverse inhibitor control description.
Lock-up Control
From sensor input signals, the PCM determines whether to turn the lock-up ON or OFF, and activates lock-up control
solenoid valve A and/or B accordingly. Lock-up does not occur until the engine is warm. The combination of driving sig-
nals to lock-up control solenoid valves A and B and the linear solenoid pressure is shown in the table below.
Lock-up ConditionsLock-up Control
Solonoid Valve A
Lock-up Control
Solenoid Valve B
Linear Solenoid
Pressuro
LOCK-Up \JrrOFFOFFHigh
Lock-up, HalfONDuty operation
OFF - ON
Lock-up, FullONONHish
Lock-up
during decelerationONDuty operation
OFF - ONLow
(cont'd)
14-17
www.emanualpro.com
Description
Hydraulic Control
The hydraulic control system is controlled by the ATF pump, valves, accumulators, and electronically controlled solenoids.
The ATF pump is driven by splines on the end of the torque converter which is aftached to the engine. Fluid from the ATF
pump flows through the regulator valve to maintain specified pressure, through the main valve body, to the manual valve,
directing pressure to each clutch. The valve body includes the main valve body, the regulator valve body, the lock-up
valve body, the secondary valve body, the servo body, the linear solenoid, the shift control solenoid valve Ay'B assembly,
and the lock-up control solenoid valve A/B assembly. The shift control solenoid valve A,/B assembly and the linear
solenoid are bolted on the outside of the transmission housing. The lock-up control solenoid valve A,/B assembly is bolted
on the outside of the torque converter housing.
LINEAR
SHIFT CONTROLSOLENOID VALVE A/BASSEMBLY
SECONDARY VALVEBODY
REGULATORVALVE BOOY
VALVE BODY
SOLENOID VALVE A/BASSEMELY
N
ATF PUMP GEARS
14-24
www.emanualpro.com
Hydraulic Flow
General Chart of Hydraulic Pressure
ATF pump - Regulator Valve -a LinePressure 5 Modulator Pressure - Linear Solenoid
| - Clutch Pressure
L- Toroue Converter Pressure
L LUbrication Pressure
Distribution ol Hydraulic Pressure
. Regulator Valve -"- Torque Converter Pressure
L- Lubrication PressureI To regulate Line Pressure
. Manual Valve To select Line Pressure - Clutch Pressure
. Modulator Valve Modulator Pressure -- ---- Shift Control Solenoid Valves
f- Lock-up Control Solenoid valves
L Linear Solenoid
. 1-2 Shift Valve ---
. 2-3 Shift Valve -- t- Clutch Pressure
. 3-4 Shift Valve I
PORT NO,DESCRIPTION OF PRESSUREPORT NO,DESCRIPTION OF PRESSURE
1LINE15lST-HOLD CLUTCH
LIN E1ST-HOLD CLUTCH
't'LINE171ST-HOLD CLUTCH
2LINE181ST-HOLD CLUTCH
3LINE202ND CLUTCH
3' LINE20A2ND ACCUMULATOR
3"LINE303RD CLUTCH
LINE404TH CLUTCH
LINE414TH CLUTCH
LINELINEAR SOLENOID
590TOROUE CONVERTER
MODULATE91TOROUE CONVERTER
6AMODULATE (SHIFT CONTROL SOLENOIOVALVE A)92TOROUE CONVERTER
MODULATE (SHIFT CONTROL SOLENOID
VALVE B)93ATF COOLER
IVODULATE (LOCK.UP CONTROL SOLENOID
VALVE A)94TOROUE CONVERTER
MODUTATE (LOCK-UP CONTROL SOLENOID
VALVE B)95LUBRICATION
6D'MODULATE (LOCK-UP CONTROL SOLENOID
VALVE B)TOROUE CONVERTER
7LIN E97TOROUE CONVERTER
8LINE/CPC99SUCTION
ILINExDRAIN
101ST CLUTCHHIXHIGH POSITION DRAIN
{cont'd)
14-29
www.emanualpro.com
Description
Hydraulic Flow (cont'dl
l?J Position
Line pressure {1) flows to the manual valve and the modulator valve. Line pressure (1} changes to line pressure (4) at themanual valve, and changes to modulator pressure at the modulator valve. But modulator pressure {6} does not flow toeach shift valve because shift control solenoid valves A and B are turned ON by the PCM. Line pressure (4) passes throughthe CPB valve and the CPC valve, and changes to line pressure (5), then flows to the 'l-2 shift valve. Line pressure (5) fromthe 1-2 shift valve changes to 2nd clutch pressure (20) at the 2-3 shift valve. The 2nd clutch pressure (20) is applied to the2nd clutch, and the 2nd clutch is engaged, Line pressure (4) passes through the 1-2 shift valve and the orifice, and changesto lst clutch pressure. The 1st clutch pressure {10) also flows to the 1st clutch. However, no power is transmitted becauseof the one-way clutch.
NOTE:
. When used, "left" or "right" indicates direction on the hvdraulic circuit.. The hydraulic circuit shows the '97 - 98 models (7 positions); the '99 - OO models (6 positions) issimilar.
14-32
www.emanualpro.com
E Position
Fluid flow through the torque converter circuit is the same as in N position. Line pressure (1) changes to line pressure (3)
and flows to the 1-2 shift valve. Line pressure (3) changes to line pressure (3') at the 1-2 shift valve and flows to the servo
vaive. The servo valve is moved to the right side (Reverse range position) and uncovers the port to allow line pressure (3")
to the manual valve. Line pressure (3') from the 1-2 shift valve flows through the servo valve to the manual valve and
changes to 4th clutch pressure (40). The 4th clutch pressure (40) is applied to the 4th clutch, and the 4th clutch is engaged.
R€verse Inhibitor Control
When the @ position is selected while the vehicle is moving forward at speeds over 6 mph (10 km/h), the PCM outputs the
1st speed signal to shift control solenoid valves A and B; shift control solenoid valve A is turned OFF, shift control solenoid
valve B is turned ON. The 1-2 shift valve is moved to the right side and covers the port to stop line pressure (3') to the
servo valve. Line pressure {3') is not applied to the servo valve, and 4th clutch pressure (40} is not applied to the 4th
clutch, as a result, power is not transmitted to the reverse direction.
NOTE:
. When used, "lelt" ot " right" indicates direction on the hydraulic circuit.
. The hvdraulic circuit shows the '97 - 98 models (7 positions); the '99 - 00 models (6 positions) is similar'
(cont'd)
14-37
www.emanualpro.com
Lock-up System
TOROUE CONVERTER
In E position ('97 - 98 models) and in E position ('99 -
OO models) (3rd and 4th), and E position ('97 - 98 mod-
els) and in E position with Over-Drive (O/D) is OFF (by
pressing the O/D switch) ('99 - 00 models) (3rd), pressur-
ized fluid is drained from the back of the torque convert-
er through a fluid passage, causing the lock-up piston to
be held against the torque converter cover, As this takes
Dlace, the mainshaft rotates at the same speed as th8
engine crankshaft. Together with the hydraulic control,
the PCM optimizes the timing of the lock-up system.
Under certain condltions. the lock-up clutch is appli€d
during deceleration, in 3rd and 4th gear.
The lock-up system controls the range of lock-up sccord-
ing to lock-up control solenoid valves A and B, and ths
linear solenoid. When lock-up control solenoid valves A
and B activate. modulator pressure changes. Lock-up
control solenoid valves A and B are mounted on the out-
side of the torque converter housing, and the linear
solenoid is mounted on the transmission housing. They
are controlled bv the PCM.
The table below shows the lock-up conditions for lock-up
control solenoid valves and linear solenoid pressure.
LINEAR SOLENOID PRESSURE
(cont'd)
LOCK.UP CONTROL' VALVE
LOCK.UP CONTROLSOLENOID VALVE
AB
MODULATORPf,ESSURE
MAINSHAFT
COUNTERSHAFT
SUB.SHAFT
Lock-up
Conditions
Lock-up Conirol
Solenoid valveLinaal
Solenoid
PrgssulsAB
Lock-up OFFOFFOFFHigh
Lock-up, HalfONDuty operation
OFF - ONLow
Lock-up, FullONONHigh
Lock-up
during
deceleration
ONDuty operation
OFF - ON
RELIEF VALVE
LOCK'UP TIMINGVALVE
COOLER RELIEF VALVE
ATF COOLERATF STRAINER
ATF PUMP
14-39
www.emanualpro.com
Terminal NumborSignalDescriptionMeasuring Conditions/Terminal Voltage
D1LCALock-up control solenoid valve A
control
During lock-up conditions: Baftery voltage
During no lock-up condition: 0 V
D2SHBShift control solenoid valve B
control
Battery voltage in following positions:
. E, E and positions
. E, -ql, and E positions in lst and 2nd gear
0 V in following positions:
. E, E;, and E positions in 3rd gear
. E and E positions in 4th gear
. E, El, and El positions
D3LCBLock-up control solenoid valve B
control
During full lock-up conditions: Battery voltage
During half lock-up conditions; Pulsing signal
D4Not used
D5VB SOLPower supply for solenoid valves
(Under-hood Fuse 15)
With ignition switch ON (ll); Battery voltage
With ignition switch OFF: 0 V
D6ATP RAy'T gear position switch
B position input
In E position: OV
In other than E position: Baftery voltage
D7SHAShift control solenoid valve A
control
Battery voltage in following positions:
. E position
. E, E, and E positions in 2nd and 3rd gear
. E position
0 V in following positions:
. E position. E. E, and E positions in lst gear
. Erl and E positions in 4th gear
.EandEpositions
D8
{'98 model}
ATP D3Ay'T gear position switch
E position input
In E position: 0V
In other than E position: Baftery voltage
D8
('99 - 00 models)
O/D SWOver-Drive (O/D) switch signal
input
When Over-Drive {O/D) is OFF (O/D OFF
indicator light is ON): 0 V
When Over-Drive {O/D) is ON {O/D OFF
indicator light is oFF): Battery voltage
D9ATP D4A/f gear position switch
E position input
In E position: 0V
In other than E position: 5 V
D10NCCountershaft sDeed sensor inoutDepending on vehicle speed: Pulsing signal
when vehicle is stopped: Approx.0 V
Dl1NMMainshaft speed sensor inputDepending on vehicle speed: Pulsing signal
When engine is stopped: Approx. 0 V
D12NMSGMainshaft speed sensor ground
D13ATP NPA,/T gear position switch E and
El positions input
InEandEpositions: 0V
In other than E and m position: 5 V
D14AlP 2A/T gear position switch
El position input
InE position; 0V
In other than E position: Battery voltage
D15ATP 1A,/T gear position switch
E position input
InEposition:0V
ln other than El position: Battery voltage
D16NCSGCountershaft speed sensor
grouno
PCM CONNECTOR D (16P)
14-55
www.emanualpro.com
Lock-up Control Solenoid Valve A/B Assembly
Test
1.
2.
Disconnect the 2P connector from the lock-up con'
trol solenoid valve A'lB assembly.
Measure the resistance between the No. 2 terminal
(solenoid valve A) of the connector and body
ground. and bet\iveen the No. 1 terminal (solenoid
valve B) and body ground.
STANDARD: 12 - 25 o
LOCK-UP CONTROLSOLENOID VALVECONNECTOR I2P)
Replace the lock-up control solenoid valve A/B
assembly if the resistance is out of specification
lf the resistance is within the standard, connect the
No. 1 terminal of the connector to the battery positive
terminal. A clicking sound should be heard Connect
the No. 2 terminal to the battery positive terminal. A
clicking sound should be heard. Replace the lock-up
control solenoid valve Ay'B assembly if no clicking
sound is heard when either terminal is connected to
the banerv Dositive terminal.
Check the lock-up control solenoid valve fluid pas-
sages for dust or debris, and replace as an assem
bly, if necessary.
Terminalside ofmale terminals
LOCK.UP CONTROL
Replacement
NOTE: Lock-up control solenoid valves A and B must be
removed/replaced as an assembly.
1. Remove the mounting bolts and the lock-up control
solenoid valve A,,/B assembly.
LOCK.UP CONTROL6 x 1.0 mm SOLENOIO VALVE12 N.m 11.2 kgf.m,8.7 lbf.ft) A/B ASSEMBLY
Replace.Clean the mounting surfaceand flu id passages.
2.Clean the mounting surface and fluid passages, and
install a new lock-up control solenoid valve IVB with
a new filter/gasket.
Check the connector for rust, dirt, or oi!, and recon-
nect it securely.
oa
14-135
www.emanualpro.com