1996 HONDA CIVIC ac clutch circuit

Secondary Valve Body
The secondary valve body contains the PH regulator valve. the clutch reducing valve' the start clutch valve accumulator'
and the shift inhibitor valve
PH Regulator Valve
The pi regulator valve maintains hydraulic pressure supplied from the ATF pump. and supplies PH pressure to the
hvdraulic control circuit and the lubrication circuit. PH pressure is regulated at the PH regulator valve by the PH control
pressure (PHC) from the PH control valve.
Cluteh Reducing Valvo
The clutch reducing valve receives PH pressure from the PH regulator valve and regulates the clutch reducing pressure
(cR). The clutch reducing valve supplies clutch pressure (cR) to the manual valve and the start clutch control valve' and
supplies signal pressure to the PH-PL pressure control valve. the shift control valve, and the inhibitor solenoid valve'
Start Clutch Valv€ Accumulator
The start clutch vatve accumutator stabilizes the hydraulic pressure that is supplied to the start clutch'
Shift Inhibitor Valve
The shift inhibitor valve switches the fluid passage to switch the start clutch control from electronic control to hydraulic
control when the electronic control system is faulty. lt also suppliss clutch reducing pressure (cR) to the pitot regulator
valve and the pitot lubrication pipe.
START CLUTCH VALVE
SECONDARY VALVEBODY
SHIFT INHIBITOE VALVE
(cont'd)
PH REGULATOR VAL
REDUCING VALVE
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Shift Valve BodY
The shift valve body contains the shift valve and the shift control valve. Both are ioined to the shift control linear solenoro.
r tl'ft1il1rf"","" is controred by shift varve pressure (sV) from the shift contror varve. The shift varve distributes pH
pi""aur" "nO PL pressure to drive pulley and the driven pulley' to shift the transmission'
t t*"rilf:::lr';ivarve contrors the shift varve in accordance with the throttre opening and vehicle speed rhe shift
control valve is convorr"o uv ti" "iirt "ontrol linear solenoid, which is controlled by the TcM or PcM When the elec-
tronic control system is faulty, t;; snift controt uutue "witches the shift inhibitor valve to uncover the port leading the
pitot regulator pressure to the start clutch
CONTROL VALVE
VALVE BODY
T;J:"i"""1ff"t""ilody contains the manuar varve and the reverse inhibitor varve. The manuat varve bodv is borted to the
intermediate houslng
. ManualValve
The manual valve mechanicallY uncovers/covers the fluid passage according to the shift lever position'
'
ff:e;;;.'::'?Xftl::T",* is contro ed by the reverse inhibitor pressure (Rl). lt intercepts the hvdraulic circuit to the
reverse brake while the vehicle is moving forward at speeds over approximatelv 6 mph (10 km/h)'
REV€RSE INHIBITORVALVE
MANUAL VALVEBODY
SHIFT CONTROL
MANUAL VALVE
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E position, at middle sPeed range
Asthespeedofthevehic|ereachestheprescribedVa|ue,theshiftcontro||inearsolenoidisactivatedbytheTcMorPcM'
Theshiftcontro||inearso|enorocontroIsttresniftcontroIVa|vetoactivateshiftVa|vepressure(SV)'c|utchreducingpres-
sure (CR) trom the clutch reduclng valve becomes shift valve pressure (SV) at the shift control valve Shift valve pressure
(SV)flowstothe|eft"noottr'"st'ittu"tue.theshiftVa|Vetotherightsideandpositioningitinthemidd|eofitstrave|.The
shift valve covers th" pon ao ",oo nLior".irr" tiHl a ,tr" pulleys, and uncovers the port leading low pressure (PL) to the
pu eys. The drive pu ey and tne oriJen priLy |."""iu" to* pressure (PL). At this time, the pulley ratio is in the middle'
Pressure remains to apply the forward clutch and the start clutch'
NOTE: When used, "|eft" or "right" indicates direction on the hydraulic circuit'
(cont'd)
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Description
Hydraulic Flow (cont'd)
@ position, at high spe6d range
As the speed of the vehicle reaches the prescribed value, the shift control linear sol€noid moves the shift contror vatve toincrease shift valve pressure (SV) at the left end of the shift valve. ttre srrit vatve moves to the right side compared to itsposition at the middle pulley ratio. The shift valve uncovers the port leading high pressure (pxito ttre d.ve puley anduncovers the port leading low pressure (PL) to the driven pulley. The drive pu|ey receives high pressure (pH) and the driv-en pulley receives low pressure (pL). The pulley ratio is high.Pressure remains to apply the forward clutch and the start clutch,
NOTE: When used, "left,, or,,right" indicates direction on the hydraulic circuit.
L
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E position
The flow of fluid up to the drive pulley, the driven pulley' and the clutch reducing valve is the same as in E position The
pulley ratio is low b"car"" tt " o riu",i'prti"vi"""v"" t'igtr pressure.(pH) and the drive pulley receives low pressure {PL).
The manual valve is shifted into the B position, and it uncovers the port that leads reverse brake pressure (RVS) to the
reverse inhibitor valve. The inhibitoi Jenoid turns off by means of the TcM or PcM, and reverse inhibitor pressure (Rl) is
appliedtotherightendofthe,"u",""int,iui.o,u,|ve.Thereverseinhibitorva|vemovestothe|eftside,anduncoversthe
port that leads reverse brake pr"a"ur" tivst,o,he reverse brake. clutch reducing pressure (cR) becomes reverse brake
pressure (RVS) at the manuat *r"-, "nJ tro*" to the reverse brake. The reverse brake is engaged, and it locks the ring
gear.
NOTE: When used, "|eft" or "right" indicates direction on the hydraulic circuit'
(cont'd)
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Description
Hydraulic Flow (cont'd)
lll position, when th€ electronic control system is fauhy.
when the electronic control svstem (linear solenoids and sensors) is faulty, the transmission uses the pitot pipe pressure(PP) to 311o- rh" u"hicle to drive.
when all linear solenoids and sensors are off because of a faulty electronrc control system, clutch reducing pressure (cR)flows to the start clutch control valve, the manual valve, the PH-PL control valve, and the shift control valve. clutch reduc-ing pressure (cR) becomes shift varve pressure (sV) at the shift contror varve, and shift varve pressure {sv) is appried tothe left end of the shift valve and the right end of the shift inhibitor valve. The shift valve moves to the right side. anduncovers the pon that leads high pressure (PH) to the drive pulley and uncovers the po.t tlr"t r""1" ro,,"-pressure (pL) tothe driven pulley At this time, the pulley ratio is high, The shift inhibitor valve moves to the left side, and uncovers theport that leads shift inhibitor pressure (Sll to the pitot lubrication pipe and the pitot regulator valve. tne prtot lubricationpipe discharges fluid inside of the pitot flange, and discharged fluid enters into the pitot pipe and it is applied to the leftend of the pitot regulator valve. The pitot regulator valve moves lo the right side, and uncovers the port that leads pitotregulator pressure (PR) to the shift inhibitor valve. Pitot regulator pressure {pR) becomes start clutch pressure {sc1 at theshift inhibitor valve, and is applied to the stan clutch. The stan clutch rs engaged. The forward clutch pressure (FWD) isapplied to the forward crutch, and the forward crutch is engaged. This alows the vehicre to drive.
NOTE: When used. "|eft" or ,,right', indicates direction on the hydraulic circuit.
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I.

E] position, when the elestronic Gontrol system is faulty'
The flow of tluid up to the drive pulley, the driven pulley' and the start clutch is the same as in El position
The manual valve is shifted into the lE position' and it uncovers the port that leads reverse brake pressure {RVS} to the
reverse inhibitor valve. Reverse ,"nlu-i,"ip*r""i" (Rl) is applied to.the right end of the reverse inhibitor valve because of
afaultyinhibitorsolenoid.The'"t'",""inftiUito'valvemovestotheleftside'anduncoverstheportthatleadsreverse
brake pressure {RVS) to the ,"u"r." ir"t"- cru,ch reducing pressure (cR) becomes reverse brake pressure (RVS) at the
manual valve, and,lows to the ,e
"rs" lr"re. ttre reverse brake is engaged and locks the ring gear' This allows the vehi-
cle to drive in reverse.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit'
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PGM Terminal Voltage/Measuring Conditions ('99 - 00 Modelsl
A/T Control System
The PCM terminal voltage and measuring conditions are shown for the connector terminals that are related to the A/T con-trol system. The other PCM terminal voltage and measuring conditions are described in section 11.
PICM Connoctor Terminrl Location3
Terminal NumberSignalDescriplionMeasuring Condhions/Torminal Voltage
A7ATP DA,/T gear position switch
E position input
InEposition:OV
In other than E] position: Approx. 1O V
A9ATP NPA/T gear position switch
@ and S positions input
In E and El positions: 0 V
In other than E] and E position: Approx. 1O V
A10Timing and adjustment service
check signal
With ignition switch ON {ll} and service check
connector oDen: 5 V
With ignition switch ON (ll) and service check
connector connected with soecialtool:0 v
ATP LA,/T gear position switch
I position input
In E position; OV
In other than E position: Approx. 10 V
STOP SWBrake switch signal outputBrake pedal depressed: Battery voltage
Brake pedal released: 0 V
PCM CONNECTOR B I25P}
Terminal NumberSignalDescriptionMoasuring Condhions/Terminal Vohage
B1IGPlPower supply circuit from main
relay
With ignition switch ON (lll: Battery voltage
With ignition switch OFF: 0 V
82PG1Ground
B8HLC LSMPH-PL control linear solenoidpower supply neqative electrode
B9IGP2Power supply circuit from main
relay
With ignition switch ON (lll: Battery voltage
With ignition switch OFF:0 V
810PG2Ground
817HLC LSPPH-PL control linear solenoid
power supplypositive electrode
With ignition switch ON {ll): Pulsing signal
818SC LSMStart clutch control linear
solenoid power supply negative
electrode
s20LGIGround
821VBUBack-up power supplyAlways battery voltage
B22Ground
825SC LSPStan clutch control linear
solenoid power supply positive
electrode
With ignition switch ON (ll): Pulsing signal
t
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