1996 HONDA CIVIC Elect

Electronic Control SYstem
The electronac controt system consrsts of a Powertrain control Module (PcM), sensors, a Iinear solenoid and four solenoid
valves, shifting and lock-up are electronically controlled for comfortable driving under all conditions The PCM is located
below the dashboard, under the front lower panel on the passenger's side
PGM-FIControl Sy3tem
A/T Control SYstom
Shift Control
Lock-uD Control
14-13

Description
Electronic Control System (cont'd)
Shift Control
The PCM instantaneously determines which gear should be selected by various signals sent from sensors, and actuatesthe shift control solenoid valves A and B to control shifting. Also. a Grade Logic Control System has been adopted to con-trol shifting in E position while the vehicle is ascending or descending a slope, or reducing speed.
PoshionGearShift Control Solenoid
Vslve A
Shift Control Solenoid
Valve B
8,tr
1stOFFON
2ndONON
3rdONOFF
E4thOFFOFF
tr2ndONON
E-ReverseONOFF
*See page 14-31 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 controlsolenoid valve A and/or B accordingly. The combination of driving signals to lock-up control solenoid valves A and B andthe linear solenoid pressure is shown in the table below.
Lock-up ConditionsLock-up Control
Solenoid Valvo A
Lock-up Control
Solenoid Valve B
Linoar Solonoid
Prggguro
Lock-up OFFOFFOFFHigh
Lock-up, HalfONDuty operation
OFF * ONLow
Lock-up, FullONONHigh
LOCK-Up
during decelerationONDuty operation
OFF - ON
a
14-14

Description
Electronic Control System {cont'dl
Ascending Control
When the PCM determines that the vehicle is climbing a hill in E position, the system oxtends the sngagement area of2nd gear and 3rd gear to prevent ths transmission from fr€quently shifting between 2nd and 3rd gears, and between 3rdand 4th gears, so the vehicle can run smooth and have more power when needed. There are two ascending modes withdifferent 3rd gear driving areas according to the magnitude of a gradient stored in the pCM.
NOTE:
. The PCM memory contains shift schedules between 2nd and 3rd gears, and between 3rd and 4th gears that enable thePCM's fuzzy logic to automatically select the most suitable gear according to the magnitude of a gradient. Fuzzy logic is a form of artificial intelligence that lets computers respond to changing conditions much like a humanmind would,
Dssconding Control
When the PCM determines that the vehicle is going down a hilt in E position, the shift-up speed from 3rd to 4th gearwhen th€ throftle is closed becomes faster than the set speed for flat road driving to widen the 3rd gear driving area.This, in combination with engine braking from the deceleration lock-up, achieves smooth driving when the vehicle isdescending. There are two descending modes with different downshift (4 - 3) schedules according to the magnitude of agradient stored in the PCM. When the vehicle is in 4th gear, and you are decelerating on a gradual hill, or when you areapplying the brakes on a steep hill, the transmission will downshift to 3rd gear. When you accel6rate, the transmission willthen return to 4th gear.
ASCENDING MODEDESCENDING MODE
4TH SHIFTING
L.
F
CHARACTERISIICSCONTROL AREA
ff.1"11", vehicr. 3pe€dff;Tlr., vohicre speed
GRADUAL ASCENOINGCONTROL AREA
Docel6ration Control
When the vehicle goes around a corner. and needs to first decelerate and then accelerate. the rcM sets the data for decelerationcontrol to reduce the number of times the transmission shifts. When the vehicle is decelerating from speeds above 26 mph(41 km/h), the rcM shifts the transmission from 4th to 2nd earlier than normal to cope with upcoming acceleration.
14-16

Description
Electronic Control System (cont'dl
Circuit Diagram and Terminal Locations -'99 - O0 Models
GNTONSWICH,,--b. rcj
LI
LOCK.UPCONIFOLSOLEI\Q D VALVE A
LOCK UP CON'IROLSOLENODVALVEB
SH FI CONTROL
SHIFTCONTFOLSOLENOIDVALVEE
L NEAF SOLEIOIO
PG2
IGP2
v3u
vcc2
sc2
6NII ON SWICH
14-18

Hydraulic Control
The hydraulic control system is controlled by the ATF pump, valves, accumulators, and electronically controlled solenoids'
TheATFpUmpisdrivenbysp||nesontheendofthetorqueconverterWhichisattachedtotheengine.F|uidfromtheATF
pumpf|owsthroughtheregu|atorva|vetomajntainspecifiedpressurethroughthemainva|vebodytothemanuaIva|ve'
directingpressuretoeachofthec|utches.Theva|vebodyinc|udesthemainvaivebody,theregu|atorvalvebody,the
|ock-upva|vebody,thesecondaryVa|vebody,theservobody,theIinearso|enoid,theshiftcontro|so|enoidva|velVB
assembly, and the lock up control solenoid valve A/B assembly. The shift control solenoid valve Ay'B assembly and the lin-
ear 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
SHIFT CONTROLSOLENOIO VALVE A/8
ASSEMBLY
LINEAR SOLENOID
SERVO BOOY
REGULATORVALVE BODY
VALVE
VALVE BOOY
(cont'd)
CONTROLSOLENOID VALVE A/BASSEMBLY
ATF PUMP GEARS
14-19

Description
Hydraulic Flow
General Chart ol Hydraulic PressureATF Pump- pegurator varve -_l- Line pressure -f- Modurator pressure - Linear sorenoid
| -Clutch pressure
-Torque Converter pressure
t-Lubrication Pressure
Distribution of Hydraulic Pressur€. Regulator Valve -]- Torque Converter pressure
F_ Lubrication pressure
i- To regulate Line pressure
. Manual valve _ To select Line pressure _ clutch pressure
' Modulator Valve i/odulator pressure _ ___f_ Shift Control Solenoid Valves
F_ Lock_up Control Solenoid ValvesL_ Linear Solenoid
. 1-2 Shift Valve - l. 2-3 Shift Valve - 1- Ctutch pressure. 3-4 Shift Valve
lra
PORT NO.DESCRIPTION OF PRESSUREPORT NO.DESCRIPTION OF PRESSUREPORT NO.DESCRIPTION OF PRESSURE
1LINE6B
MODULATE(SHIFT CONTROL
SOLENOID VALVE B)
414TH CLUTCH
LINEMODULATE(LOCK-UP CONTROL
SOLENOID VALVE A)
56LINEAR SOLENOID
LINE6D
MODULATE(LOCK-UP CONTROL
SOLENOID VALVE B)
90TOROUE CONVEBTER
2LINE6D'
MODULATE
(LOCK-UP CONTROL
SOLENOID VALVE B)
91TOROUE CONVERTER
LINE7LINE92TOROUE CONVERTERLINE8LINE/CPC93ATF COOLER3"LINE9LINE94TOROUE CONVERTER4LIN E'101ST CLUTCH95LUBRICATION
LINE202ND CLUTCHYOTOROUE CONVERTERLINE20A2ND ACCUMULATOR97TOROUE CONVERTER5LINE99SUCTION
MODULATE303RD CLUTCHXDRAIN
6A
MODULATE(SHIFT CONTROL
SOLENOID VALVE A)
404TH CLUTCH
14-24

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

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
\-
14-42