PCM HONDA CIVIC 1996 6.G Workshop Manual

Continuously Variable Transmission (CVTI
Special Tools ................ 14-194
Description .................... 14-195
Clutches/Reverse Brake/Planetary
Gear/Pulleys .......... 14-198
power Flow ..............,..... 14-200
Electronic Control SYstem(,96 - 98 Modets) ......14-203
Electronic Control System
('99 - oo Models) " 14-205
Hydraulic Control '....... 14-208
Hydraulic Flow .'..-.....'... '14-212
Park Mechanism .....-...'.' 14-222
Eleqtrical Systom
Component Locations'96 - 98 Models """"""' 14-224,99 - 00 Modets ............. 14-225
TCM Circuit Diagram ('96 - 98 Models) ............. 14-226
TCM Terminal Voltage/Measuring Condiiions ('96 - 98 Models) '.... 14-228
PcM Circuit Oiaqram{A/T Control System: '99 - 00 Models} ...--.... 14-230
PCM Terminal Voltage/Measuring Conditions('99 - 00 Models)
A/4 Control System .'.'...14-232
Troubleshooting Procedures ... . .... .....',........."' '14-234
Symptom-to-ComPonent Chart
Electrical System - '96 - 98 Models ......'..... '14-234
Electrical System -'99 - 00 Models ..'....-..-. '11-210
Electrical Troubleshooting
Troubleshooting Flowcharts('96 - 98 Models) """'11-242
Troubleshooting Flowchart
('99 - 0O Modets) ...... 14-265
Linear Solenoids/lnhibitor Solenoid
Test ......................... . ...... 14-29f
Drive Pulley/Driven Pulley/Secondary Gear
Shaft Speed Sensors
Replacement .........'...... .14-292
Start Clutch Control
Start Clutch Calibration Procedure ....... ....,. 14-293
Hydraulic SYstem
Symptom-to-ComPonent Chart
Hydraulic System '.'.......14-294
Road Test ............................ 14-296
Stall Speed
Test......................... ...... 14-294
Fluid Level
Checking/Changing ....... 14-299
Pressure Testing ................. 14-300
Lower Valve BodY AssemblY
Replacement ..........,... 14-302
ATF Filter
Removal/lnstallation ..... 14-303
Transmission
Transmission
Removal ........... . 14-304
lllustrated Index
Transmission/Lower Valve BodY
Assembly ................. 14-308
Transmission Housing/Flywheel Housing ... 14-310
End Cover/f ntermediate Housing ..........'.'.... 14-312
Transmission Housing/Lower Valve Body Assembly
Removal ..........'.... .. " 14-314
Transmission Housing/Flywhesl Housing
Removal ................. ........ 1+316
End Cover/lntermediate Housing
14-318Removal .........,...............
Manual Valve Body
Disassembly/lnspection/Reassemblv .'.'.'..... 1 4-320
Forward Clutch
lltustrated Index ........................................ 14-321
Disassemblv .................. 14-322
Reassemblv , ,, . ',','......14-324
Secondary Gear Shaft
25 x 35 mm Thrust Shim Selection ..'.'....-... 14-324
Differential
lllustrated lndex ...,.....................,.,...-.-.-...'... 14-329
Backlash Inspection .-....14-329
Bearing Replacement ......'........'....'... ....'... 14-330
Differential Carrier Replacement ........'........ 14-330
Oil Seal Removal ........... 14-331
Oil Seal Installation/Side Clearance ....... . . 14-331
Flywheel Housing Input Shaft Oil Seal
Replacement .....,.... ...'.'.. 14-333
Transmission Housing Bearings
Driven Pulley Shaft Bearing
Replacenient ...................'. . ...................'.. 14-334
Secondary Gear Shaft Bearing
Reolacbment ...................... . .......... . ........ 14-335
Flywheel Housing Beating
Secondary Gear Shaft BearingReo1acement..................,........................... 14-335
Ring Gear Bearing
Replacement......... ........ 14-336
Control Shaft Assembly
Removal/lnstallation ....................'........... 14-336
Transmission
Reassembly .................. 14-338
Flywheel/Drive Plate .. . ...... . ...... ... . ....-.....'.'...14-341
Transmission
lnstalation ..................... 14-348
Cooler Flushing .'......... 14-352
shift cable
Removal/lnstallation....'........." """ 14-354
Adjustment .......'........ 14-355
Shift Lever ........................,. 14'356
Shift Indicator Panel
Adjustment ................ 14-357
ATF Cooler/Hoses
lnsta llation ......,,...... .... 14-357

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)
14-195
,!

Electronic Gontrol System ('99 - 00 Modelsl
The electronic controt system conststs 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'
fn"pCVirlocatedbelowthedashboard,underthekickpanelonthepassenger'sside'
The pCM controls the transmassion to reduce engine speed and retain the engine's cooling efficiency when the vehicle is
driven with full throftle acceleration
lf the vehicle is continuously driven at lull throttle acceleration, the PCM regulates the pulley hydraulic pressure to
increase the pulley ratio which. as the result, reduces the engine speed and retains the designed cooling efficiency After
the vehicle has been driven at a lower engine speed for a while, the PCM increases the pulley ratio to the original ratio'
i"i ".nl",rr starting in the E position, the PcM cuts off the ,Vc clutch (if the A/c is on) and increases the engine speed to
900 rpm when the transmission is shifted to the E position'
The start clutch functions to make smooth starting possible. To let the start clutch function properly, the PcM regulates
the start clutch hydraulic pressure based on the engine's negative pressure memorized in the E position'
FCM
s*o.d.ry G..t Sh.h
(cont'd)
14-205

Description
Electronic Control System ('99 - 00 Modelsl (cont'dl
Grade Logic Control System
How it works:
The PcM compares actual driving conditions with memorized driving conditions. based on the input from the vehiclespeed sensor, the throttle position sensor, the manifold absolute pressure sensor, the engine coolant temperature sensor,the brake switch signal, and the shift lever position signal, to control shifting while the vehicle is ascending or descendinga slope.
Ascending Control
When the PCM determines that the vehicle is climbing a hill in E position, the system selects the most suitable shiftschedule (pulley ratio) according to the magnitude of a gradient. so the vehicle can run smooth and have more powerwhen needed. There are three ascending modes with different shift schedules according to the magnitude ot a gradient inthe PCM.
Descending Control
when the PCM determines that the vehicle is going down a hill in E position. the system selects the most suitable shiftschedule (pulley ratio) according to the magnitude of a gradient. This, in combinstion with engine braking, achievessmooth driving when the vehicle is descending, There are three descending modes with different shift schedules accord-ing to the magnitude of a gradient in the PCM.
L
14-206

Description
Hydraulic Control
The hydraulic control system is controlled by the ATF pump. the valves, and the solenoids. The ATF pump is driven by theinput shaft. The ATF pump and the input shaft are linked by the ATF pump drive chain and the sprockets, The inhibitorsolenoid valve and the linear solenoids. which are located on their valve body, are controlled by the TCM or pcM. Fluidfrom the ATF pump flows through the PH regulator valve to maintain specified pressure to the drive pulley, the driven pul-ley, and the manual valve,
The lower valve body assembly includes the main valve body, the PL regulator valve body, the shift valve body, the startclutch control valve body, and the secondary valve bodv.
Main Valve Eody
The main valve body contains the pH control valve, the rubrication valve, and the pitot regulator valve.
PH Control Valve
The PH control valve supplies PH control pressure (PHCI in accordance with the pH-pL control pressure (HLc), and sup-plies PH control pressure to the PH regulator valve, which also regulatss PH pressure. At kick-down, it increases pHcontrol pressure which increases the high (PH) pressure. This shortens the shift speed by releasing the reverse inhibitorpressure (Rl)from the inhibitor solenoid valve.
Lubrication Valve
The lubrication valve controls the lubrication pressure to each shaft and maintains lubrication pressure. When rne pres-sure is too high, the spring is compressed. This moves the lubrication valve and opens the fluid leak passage.
Pitot Regulalor Valv6
The pitot regulator valve controls the start clutch pressure (SC) in accordance with the engine speed, when the electron-ic control system is faulw.
MAIN VAIVEBODY
L.
14-208

Description
Hydraulic Control {cont'dl
PL Regulator Valve Body
The PL regulator valve body contains the PL regulator valve and the PH-PL control valve. which is joined wirh the pH-pL
control linear solenoid. The inhibitor solenoid is bolted on the pL regulator valve body.
. PL Regulator Valve
The PL regulator valve supplies low p.essure (pL) to the pulley to eliminate steel belt slippage.The PL pressure is controlled by the pH-pL control pressure (HLC).
. PH-PL Control Valve
The PH-PL control valve controls the PL regulator valve according to engine torque. The PH-PL control valve suooliesPH-PL control pressure (HLC) to the PH control valve to regulate PH pressure higher than pL pressure. The pH-pL con-trol valve is controlled by the PH-PL control linear solenoid. which is controlled by the TcM or pcM,
. Inhibitor Solenoid
The inhibitor solenoid controls the reverse inhibitor valve by turning on and off. Also, the inhibitor solenoad controls pH
control pressure (PHC) by applying reverse inhibitor pressure (Rl) to the PH control valve. The inhibitor solenoid is con-trolled by the TCM or Pclvl.
Start Clutch Control Valv€ Body
The start clutch control valve body contains the start clutch control valve. Both are joined to the stan clutch control linearsolenoid.
. Start Clutch Control Valve
The start clutch control valve controls start clutch engagement according to the throttle opening. The start clutch con,trol valve is controlled by the stan clutch control linear solenoid, which is controlled bv the TCM o. pCM.
START CLUTCH CONTROLvAt-vE
LOWER VALVE BODYASSEMBI-Y
PH.PL CONTROLLINEAR SOLENOID
I.
14-210

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
14-211

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)
14-215

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)
14-217

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.
14-218