1996 HONDA CIVIC Valve cover

Description
The Continuously Variable Transmission (CVT) is an electronically controlled automatic transmission with drive and driv
en Oullevs, and a steel belt. The CVT provides non stage speeds forward and one reverse. The entire unit is positioned in
line with the engine.
Transmission
Around the outside of the flywheel is a ring gear which meshes with the starter pinion when the engine is being staned.
The transmission has four parallel shafts: the input shaft, the drive pulley shaft. the driven pulley shaft, and the secondary
gear shaft. The input shaft is in line with the engine crankshaft. The drive pulley shaft and the driven pulley shaft consist of
movable and fixed face pulleys. Both pulleys are linked by the steel belt.
The input shaft includes the sun gear. The drive pulley shaft includes the forward clutch which mounts the carrier assem-
bly on the forward clutch drum. The carrier assembly includes the pinion gears which mesh with the sun gear and the ring
gear. The ring gear has a hub-mounted reverse brake disc.
The driven pulley shaft includes the start clutch and the secondary drive gear which is integral with the park gear' The sec-
ondary gear shaft is positioned between the secondary drive gear and the final driven gear. The secondary gear shaft
includes the secondary driven gear which serves to change the rotation direction. because the drive pulley shaft and the
driven oullev shaft rotate the same direction. When certain combinations of planetary gears in the transmission are
engaged by the clutches and the reverse brake, power is transmitted from the drive pulley shaft to the driven pulley shaft
to provide E, E, E, and El.
Electronic Control'96 - 98 Models:
The electronic control system consists of the Transmission Control Module (TCM), sensors, three linear solenoids, and a
inhibitor solenoid. Shifting is electronically controlled under all conditions'
The TCM is located below the dashboard, behind the kick panel on the driver's side.'99 - 00 Models:
The electronic control svstem consists of a Powertrain Control Module (PCM), sensors, three linear solenoids and an
inhibitor solenoid. Shifting is electronically controlled under all conditions. A Grade Logic Control System to control shift-
ing in E position while the vehicle is ascending or descending a slope.
The PCM is located below the dashboard, under the kick panel on the passenger's side.
Hydraulic Control
The lower valve body assembly includes the main valve body, the Pressure Low (PL) reguiator valve body, the shift valve
body, the start clutch control valve body, and the secondary valve body. They are positioned on the lower part of the
transmission housing.
The main valve body contains the Pressure High (PH) control valve, the lubrication valve, and the pitot regulator valve.
The secondary valve body contains the PH regulator valve, the clutch reducing valve, the start clutch valve accumulator,
and the shift inhibitor valve. The PL regulator valve body contains the PL regulator valve and the PH-PL control valve
which is ioined to the PH,PL control linear solenoid. The inhibitor solenoid valve is bolted on the PL regulator valve body.
The shift valve body contains the shift valve and the shift control valve. which is joined to the shift control linear solenoid.
The start clutch control valve body contains the start clutch control valve, which is joined to the start clutch control linear
solenoid. The linear solenoids and the inhibitor solenoid are controlled by the TCM or PCM. The manual valve body which
contains the manual valve and the reverse inhibitor valve, is bolted on the intermediate housing.
The ATF pump assembly is located on the transmission housing, and is linked with the input shaft by the sprockets and
the sprocket chain. The pulleys and the clutch receive fluid from their respective feed pipes, and the reverse brake receives
fluid from internal hydraulic circuit.
Shift Control Mechanism
Input from various sensors located throughout the vehicle determines which linear solenoid the TCM or PCM will activate.
Activating the shift control linear solenoid changes the shift control valve pressure, causing the shift valve to move. This
pressurizes the drive pulley pressure to the drive pulley and the driven pulley pressure to the driven pulley and changes
their effective pulley ratio. Activating the start clutch control linear solenoid moves the start clutch control valve. The start
clutch control valve uncovers the port, providing pressure to the start clutch to engage it(cont'd)
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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'dl
E position
Reverse Inhibitor Conirol
lf the E position is selected while the veiicle is moving forward at speeds over 6 mph (10 km/h), the inhibitor solenoiddoesn't turn off by means of the TcM or PCM Reverse inhibitor pressure (Rl) is not applied to the reverse inhibitor valveas the reverse inhibitor solenoid turns on. The reverse inhibitor valve is kept on the right side, and covers the pon ro sropreverse brake pressure {RVS} to the reverse brake from the manual valve. Reverse brike pressure (RVs) i; not appried tothe reverse brake, and power is not transmitted to the reverse direction.
NOTE: When used, "left,' or,,right,, indicates direction on the hydraulic circuit.
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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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