1999 HONDA CIVIC Power

I
3. 3rd Gear
As the soeed of the vehicle reaches the prescribed value, shift control solenoid valve B is turned OFF by means ol the
pCM. Shift control solenoid valve A remains ON. The modulator pressure (6) flows to the right end of the 1-2 shift
valve and the left end oJ the 2-3 shift valve. The 2-3 shift valve is moved to the right side by the modulator pressure
(68). The 2-3 shift valve covers the port to stop line pressure (5) to the 2nd clutch and uncovers to the 3-4 shift valve
as the 2-3 shift valve is moved to the right side. The line pressure (5) becomes the 3rd clutch pressure (30) at the 3-4
shift valve. The 3rd clutch pressure (30) is applied to the 3rd clutch, and the 3rd clutch is engaged'
Fluid flows by way of:- Line Dressure (4) * CPB Valve - Line Pressure (5) * 1-2 Shift Valve - Line Pressure (5) * 2-3 Shift Valve
- Line Pressure (5) * 3-4 Shift Valve - 3rd Clutch Pressure (30) - 3rd Clutch
The hvdraulic pressure also flows to the 1st clutch. However, no power is transmitted because of the one-way clutch
as in 2nd gear.
NOTE: When used, "|eft" or "right" indicates direction on the hydraulic circuit.
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Description
Hydraulic Flow lcont'dl
4th Goar {E Position}
As the speed of the vehicle reaches the prescribed value, shift controlsolenoid valve A is turned OFF bymeans ofthePCM Shift control solenoid valve B remains oFF. The modulator pressure (6) flows to the left end of the t-2 shiftvalve and the left end of the 3-4 shift valve. The modulator pressure (64) in the left end of the 1-2 shift valve equalsthe modulator pressure {68) in the right end of the 1-2 shift valve, the 1-2 shift valve remains at left side by the ten-sion of the valve spring.
The 3-4 shift valve is moved to the right side by the modulator pressure (64). The 3_4 shift valve covers the port to the3rd clutch and uncovers the port to the 4th clutch as this valve is moved to the right side. The 4th clutch pressure (4.1)from the 3-4 shift valve becomes the 4th clutch pressure (40) at the manual valve. The 4th clutch pressure (401 isapplied to the 4th clutch, and the 4th clutch is engaged.
Fluid flows by way of:- Line pressure (4) * CPB Valve - Line Pressure (5) + 1-2 Shift Valve - Line pressure (5) * 2-3 Shift Valve- Line Pressure (5) - 3-4 Shift Valve - 4th Clutch pressure (41) + Manual Valve _ 4th Clutch pressure (40)* 4th Clutch
The hydraulic pressure also flows to the lst clutch. However, no power is transmitted because of the one-way crutchas in 2nd and 3rd gear.
NOTE: When used, "|eft" or "right,, indicates direction on the hydraulic circuit.
\
14-30

L
E Position
The flow of fluid through the torque convefter circuit is the same as in E position The line pressure (1) changes to the
line pressure (3) and flows to the l-2 shift valve. The iine pressure (3) changes to the line pressure (3') at the 'l-2 shift valve
and flows to the servo valve. 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, The line pressure {3') from the 1-2 shift valve flows through the servo valve to
the manual valve and changes the 4th clutch pressure (40). The 4th clutch pressure (40) is applied to the 4th clutch, and
the 4th clutch is engaged,
Reverse Inhibitor Control
When the E position is selected while the vehicle is moving forward at spe€ds 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. The line pressure (3') is not applied to the servo valve, and the 4th clutch pressure (40) is not applied to the
4th clutch, as a result, power is not transmitted to the reverse direction'
When used. 'left" or "right" indicates direction on the hydraulic circuit'
14-31

Description
Hydraulic Flow (cont'd)
lll Position
The flow of fluid through the torque converter circuit is the same as in E position. The line pressure (1) changes to theline pressure (3) and flows to the l-2 shift valve. The line pressure (3) changes to the line pressure (3,) at the 1-2 shift valveand flows to the servo valve. The servo valve is moved to the right side (Reverse range position) and uncovers the port toallow line pressure (3") to the manual valve as in @ position. The line pressure (3") from the servo valve is Intercepted bythe manual valve. However, hydraulic pressure is not supplied to the clutches, and the power is not transmitted.
NOTE: When used, "|eft" or "right" indicates direction on the hydraulic circuit.
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\
Lock-up System
Lock-up Clutch
1. Ooeration (clutch onl
with the lock-up clutch on, the fluid in the chamber between the torque converter cover and the lock-up piston is drained
off, and the converter fluid exerts pressure through the piston against the torque converter cover, As a result, the conven-
er turbine is locked to the convefter cover. The effect is to bypass the converter, thereby placing the vehicle in direct drive
LOCK.UP PISTONDAMPER SPRING
The power flows by way ot:
Engine
{
Drive plate
i
Torque converter cover
I
Lock-up piston
Damper spring
I
Turbine
Mainshaft
ODeration {clutch off}
With the lock-up clutch off, the fluid flows in the reverse of "clutch on." As a result, the lock-up piston moves away from
the converter cover, and the torque converter lock-up is releassd.
Engine
t
Drive plate
I
Torque convener cover
{
Pump
I
Turbine
Mainshaft
TOROUECOVER
(cont'd)
COI{VERTER
\
TURBNE
MAINSHAFT
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Component Locations
POWERTRAIN CONTROLMODULE (PCM)
TRANSAXLE {A/TI
COUNI€RSHAFTSPEED SENSOR
SOI,TNOID VALVEASSEMBLY
SOLENOID VALVEASSEMBLY
GEAR POSITION SWITCH
SPEED SENSOR
1+39

PCM Terminal Voltage/Measuring Gonditions ('96 - 9g Models)
A/T Control System
The PCM terminal voltage and measuring conditions are shown for the connector terminals that relate to the A"/T controlsystem. The other PCM terminal voltage and measuring conditions are described in section I l.
A l32P) Conn€ctotB I25P) ConnectorC (31P)ConngctorD (16P)Connector
PCM CONNECTOR A I32P}
Terminal NumborSignalDcacriptionMoasuring Conditions/Te.minal Voltage
A1 to A8- see section 1 I -
A9LG1Ground
A10PG1Grou nd
A11IGPlPower supply systemWith ignition switch ON (ll): 8attery voltage
With ignition switch OFF: 0 V
412 to A2l- see section I I -
Ground
423PG2Ground
A'24IG P2Power supply systemWith ignition switch ON (ll): Battery voltage
With ignition switch OFF: 0 V
A25 to A32- see section l1 -
PCM CONNECTOR B (25P}
Terminal NumberSignalDescriptionMeasuring Conditions/T6rminal Voltage
B1LS-Linear solenoid power supply
negative electrode
lgnition switch ON (ll): Pulsing signa.
82Linear solenoid power supplypositive electrode
lgnition switch ON (ll): Pulsing signal
SHAShitt control solenoid valve A
controlIn 2nd gear and 3rd gear in E, E position,
and in @, @ position: Battery voltage
In lst gear and 4th gear in E. E position: 0 V
B4LCBLock-up control solenoid valve B
control
When full lock-up: Battery voltage
When half lock-up: Pulsing signal
B5LCALock-up control sol€noid valve AcontrolWhen lock-up is ON: Battery voltage
With no lock-up: 0 V
86 to 87Not used
B8ATP D3IVT g6ar position switch @ posi-
tion signal input
lnEposition; OV
In other than E position: Battery voltage
Bg to 810Not used
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I
PCM CONNECTOR B {25P1 {cont'dl
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Vohage
811SHBShift control solenoid valve B
control
In 1st gear and 2nd gear in -q1, q11 position,
and in E] position: Battery voltage
In 3rd gear and 4th gear in lD.J, [Dr- position: 0 V
B't2SLUInterlock controlWhen ignition switch is ON (ll), brake pedal
deoressed and accelerator Dedal released: 0 V
813D4 INDD4 Indicator light controlWhen ignition switch is first turned ON (ll):
Battery voltage for two seconds
In E position: Baftery voltage
B't 4NMSGMainshaft speed sensor groundAlways: 0 V
E tcNMMainshaft speed sensor signal
input
Depending on engine speed: Pulsing signal
When engine is stopped: 0 V
816ATP RAy'T gear position switch Eposition signal input
InE position: 0V
In other than E position: Battery voltage
817ATP 2A/T gear position switch E posi-
tion signal input
InE position: 0V
In orher than E position: Battery voltage
818 to 821Not used
s22NCSGCountershatt speed sensor groundAlwaysr 0 V
B23NCCountershaft speed sensor signal
input
Depending on vehicle speed: Pulsing signal
When vehicle is stopped: 0 V
B24ATP D4Ay'T gear position switch lor posi-
tion signal input
InEposition:0V
In other than 6 position: 5 V
ATP NPA,/T gear position switch E and
N position signals input
InE and E positions: 0V
In otherthan E and N] positions: Battery voltage
PCM CONNECTOR C {31P)
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
Cl to C6- see section 11 -
c1Service check signalWith ignition switch ON (ll) and service check
connector oDen; 5 V
With ignition switch ON (ll) and service check
connector connected with sDecial tool: 0 V
C8 to Cg- see section 11 -
c10VBUBack-up power systemAlways battery voltage
C11 to C31- see section '11 -
PCM CONNECTOR D (16P}
Terminal NumberSignalDescriptionMeasuring Conditions/Terminal Voltage
Dl to D4- see section 11 -
D5STOP SWBrake switch signal inputBrake pedal depressed: Battery voltage
Brake pedal released: 0 V
D6 to D16- see section 1 l -
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