1996 HONDA CIVIC Shift pressure solenoid

Description
Hydraulic Flow (cont'd)
2nd G.!r
As tha speed of the vehicle reaches the prescribed value, shift control solenoid valve A is turned oN by means of thePCM The modulator pressure {64} in the left end of the 1-2 shift valve is r€leased by turning shift controt sotenoidvalve A oN The 1-2 shift valve is moved to the left side and uncovers the port to allow line pressure {5) to the z-3shift valve. The line pressure (5) changes to the 2nd ctutch pfessure l2O) at the 2-3 shift valve. The 2nd clutch pressure(20) is applied to the 2nd clutch, and the 2nd clutch is engaged.
Fluid flows by way of:- Line Pressure (4) + cPB varve - Line pressure (s) * 'r-2 shift varve - Line pressure (5) * 2-3 shift varve- 2nd Clutch Pressure (20) + 2nd Clutch
The hydraulic pressure also flows to the 1st clutch. However, no power is transmittod because of the one-way ctutch.
NOTE: When used, "|eft" or ,,right,, indicates direction on the hydraulic circuit.
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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.
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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'
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TOROUE CONVERTER
No Lock-up
. Lock-up Control Solenoid Valve A: OFF
. Lock-up Control Solenoid Valve B: OFF
. Linear Solenoid Pressure: High
The pressurized fluid regulated by the modulator works
on both ends of the lock-up shift valve. Under this condi-
tion, the pressures working on both ends of the lock-up
shift valve are equal, the lock-up shift valve is moved to
the right side by the tension of the valve spring alone.
The fluid from the ATF pump will flow through the left
side of the lock-up clutch to the torque convener; that is,
the lock-up clutch is in OFF condition.
NOTE: When used, "left" or "right" indicates direction
on the hydraulic circuit.
MOOULATOR PRESSURE
LINEAR SOLENOIO PRESSURE
(cont'd)
LOCK.UP CONTROLSOLENOID VALVE
RELIEF VALVE
LOCK-UP TIMINGVALVE
9 L ] I COOLER RELIEF VALVE
ATF PUMP
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Description
Lock-up System (cont'dl
TOROUE CONVERTER
Half Lock-up
. Lock-up Control Solenoid Valve A: ONLock-up Control Solenoid Valve 8: Duty Operation
OFF - ONLinear Solenoid Pressure: Low
The PCM switches the solenoid valve A on to release themodulator pressure in the left cavity of the lock_up shiftvalve. The modulator pressure in the right cavity of thelock-up shift valve overcomes the spring force; thus thelock-up shift valve is moved to the left side.The line pressure is then separated into the two pas-sages to the torque converter:
Torque Converter Inner pressure: enters into rightsade to engage lock-up clutch
Torque Converter Back pressure: enters into left sideto diseogage lock-up clutchThe back pressure (F2) is regulated by the lock-up con-trol valve, whereas the position of the lock-up timingvalve is determined by the linear solenoid Dressure andtension of the valve spring. Also the position of the lock_up control valve is determined by the back pressure ofthe lock-up control valve, torque converter pressure reg_ulated by the torque converter check valve, and modula_tor pressure determined by the lock-up control solenoidvalve B. The PCM switches the lock-up control solenoidvalve B on and off rapidly {duty operation} under certainconditions to regulate the back pressure (F2) to lock thetorque convener properly.
NOTE: When used, "left" or "right" indicates directionon the hvdraulic circuit.
MODULATOR PRESSURE
LINEAR SOLENOTD PRESSURE
LOCK.UP CONTROLVALVE
LOCK.UP CONTROLSOI.TNOID VALVE
A8
TOROUE CONVERTERCHECK VAI-VE
RELIEF VALVE
LOCK-UP TIMINGVALVE
^ L____J'r cooLER RELTEF valvE
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ATF PUMP

Troubleshooting Flowchart - Shift Control System
NOTE: Record all freeze data before vou troubleshoot.
Possible Cause
Faulty shift control system
. OBD ll Scan Tool indicates CodeP0730.. Sell-diagnosis E indicator
light indicates Code ill.
Check tor Another CoderCheck whether the OBD ll scantool or the E, indicator lightindicate another code.
Perlorm ths TroubleshoolingFlowch.rt for the indic.t.dCode(sl. Recheck tor code m730
l4'l I atter troubleshooting.
Does the oBD ll scan tool orthe E indicato'. tight indicate another code?
Test lst, 2nd, 3rd and 4th Clutch
Pressure:Measure the 1st, 2nd, 3rd and 4th
clutch pressure (see page 14119
thru 14-121).
Ropair the hydrlulic systom !snecessary {see page 14-1 19 and11-1211.
ls each clutch pressure within
the service limit?
Replace Shift Control Solenoidvalve Assembly, Linear SolenoidAssambly and Rechock:1. Replace the shift controlsolenoid valve A'/B assembly(see page 14-106).2. Replace the linear solenoidassembly lsee page 14 108).3. Turn the ignition switch OFFand reset the PCM memory byremoving the EACK UP (7.5 A)tuse in the under hood fuse/relay box for more than l0
seconds,4. Drive the vehicle at over 12mph (20 km/h) in 1st, 2nd,3rd
and 4th gear for more than 30seconds at P1 position.
5. Recheck tor code P0730 (41).
Does the OBD ll scan tool orthe Ed indicator tight indi
cate code P0730 {41)?
The swt6m is OK et this time.
NOTE: Do not continue with this troubleshooting until the causes ot any
other DTCS have been corrected.

Electrical Troubleshooting ('99 - 00 Modelsl
Troubleshooting Flowchart - Shift Control System
NOTE: Record allfreeze data before you troubleshoot.
Po33ibl. Crus6
Frulty 3hift control ryrtom
. OBD ll Scan Tool indicrtd Codem730.. Self-dirgnosis E indicatorlight indicst€. Codo 41.
Check for Anoth€. Code:Check whether the OBD ll scantool or the E indicator lightindicate another code.
Prrf orm tho Troublc!hootingFlowch.rt for th. indicrt.dCod.l3l. R.ch.ck tor cod. m730141| .tt r troubldhootlng.
Doesthe OBD llscan tool orthe E indicator light indi-cate another code?
Test 13t, 2nd, 3rd .nd 4th ClutchPrglture:Measure the 1st, 2nd,3rd and 4thclutch pressure (see page 14-119thru 14 121).
R.prir tho hydrlulic ayrtam aan.c.3t..y lr.o p!9. lil-119 rnd1+1211.
ls each clutch pressure withinthe service limit?
Roplace Shift Control SolenoidValve Asembly. Linoar Sol.noidAssembly .nd Recheck:1. Replace the shift controlsolenoid valve A/B assembly(see page 14-106).2. Replace the linear solenoidassembly {see page 14-108}.3. Turn the ignition switch OFFand reset the PCM memory byremoving the BACK UP (7.5 A)fuse in the under-hood fuse/relay box for more than 10seconds,4. Drive the vehicle at over 12mph (20 kn/h) in 1st, 2nd, 3rdand 4th gear lo. more than 30seconds at lPll position.5. Recheck for code P0730 (41).
Doesthe OBD Ilscan tool orthe E ;ndicator light indi-cate code P0730 (41)?Th. sFtcm b OK .t this time.
NOTE: Do not continue with this lroubleshooting until the causes ot anyother OTCS have beon corrected.
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