1998 HONDA CIVIC Cat transmission

lllustrated lndex
!
Refer to the drawing below for transmission disassembly/reassembly,
Clean all the parts thoroughly in solvent and dry with compressed air.
I luuricate attthe parts with oil before reassembty.
NOTE:
. This transmission uses no gaskets betvveen the major housings; use liquid gasket (PiN 08718-0001 or08718-0003)
(see page 13-41).
. Always clean the magnet @ whenever the transmission housing is disassembled.
. Inspect all the bearings for wear and operation.
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13-10

Mainshaft Thrust Shim
Adjustment
Remove the thrust shim and oil
the transmission housing.
1.gu ide plate from
THRUST SHIM
OIL GUIDEPLATE
TBANSMISSIONHOUSING
Install the 3rd/4th synchro hub, spacer collar, 5th
synchro hub, ball bearing, and thrust washer on themainshaft. Install the assembly in the transmission
h ousing.
@ gnol+lx syNcHRo HUB
THRUST WASHER
SPACER COLLAR
4.
Measure the distance @ between the end of thetransmission housing and thrust washer.
NOTE:
. Use a straight edge and vernier caliper.. Measure at three locations and average the read-
Ings.
Measure the distance @ between the surfaces ofthe clutch housing and bearing inner race.
NOTE:
. Use a straight edge and depth gauge.
. Measure at three locations and average the read-
Ings.
sTH SYNCHRO IIUB
BALL EEARING
CLUTCH
L
HOUSINGENO OF
13-36
INNER RACE OF BALL AEARING
\
5.Select the proper shim on the basis of the followingcalculations:
NOTE: Use only one thrust shim.
(Basic Formula)(B) + {C). 0.95 = shim thickness
Example of calculation:
Distance @ (2.00 mm) + Distance @= 2.09 mm
subtract the spring washer height (0.95
required thrust shim (1.14 mm)
65 mm THRUST SHIM: D16Y7 engine:
(0.09
mm)
mm)
= tne
r1
Part NumborThickness
23931 - PL3 A100.60 mm (0.0236 in)23932 - PL3 A100.63 mm 10.0284 in)c23933 - PL3 A100.66 mm {0.0260 iniD23934 PL3 - A100.69 mm (0.0272 in)
E23935-PL3-4100.72 mm 10.0283 in)
F23936-PL3-4100.75 mm 10.0295 in)G23937-PL3-A100.78 mm {0.0307 in}
23938 PL3 - A100.81 mm (0.0319 in)I23939 - PL3 At00.84 mm (0.0331 in)J23940-PL3-Ar00.87 mm (0.0343 in)
23941 - PL3 - A100.90 mm (0.0354 in)
L23942 - PL3 A100.93 mm (0.0366 in)
23943-PL3-A100.96 mm (0.0378 in)N23944 PL3 - A100.99 mm 10.0390 in)
o23945-PL3-A101.02 mm {0.0402 in}23946 - PL3 A101.05 mm (0.0413 in)o23947 PL3 - 4101.08 mm (0.0425 in)R23948-PL3-A101.11mm (0.0437 in)s23949 PL3 - A101.14 mm {0.0449 in}T23950-PL3-A101.17 mm (0.0461 in)
U23951 PL3 - A101.20 mm (0.0472 in)
23952-PL3-Ar01.23 mm {0.0484 in)
23953-PL3-A101.26 mm {0.0496 in}X23954 - P13, A101.29 mm (0.0508 in)23955 - PL3 A101.32 mm (0.0520 in)z23956-PL3-Ar01.35 mm {0.0531 in)
23957-PL3-A101.38 mm (0.0543 in)
AB239s8 - PL3 A101.41 mm (0.0555 in)AC23959 PL3 - A101.44 mm (0.0567 in)
AD23960 - PL3 A101.47 mm (0.0579 in)23961 - PL3 4101.50 mm (0.0591 in)23962 PL3 - A101.53 mm (0.0602 in)AG23963-PL3-4101.56 mm (0.0614 in)AH23964 - PL3 A101.59 mm (0.0626 in)AI23965-PL3-A101.62 mm {0.0638 in)
23966 PL3 - A101.65 mm (0.0650 in)AK23967-PL3-A101.68 mm {0.0661 in)
23968 PL3 - A101.71 mm {0.0673 in)23969-PL3-A101.74 mm (0.06a5 iniAN23970- PL3 -A101.77 mm (0.0697 in)AO23971 - PL3 - A101.80 mm 10.0709 in)

lllustrated Index
t
Refer to the drawing below for transmission disassembly/reassembly.
Clean all the parts thoroughly in solvent and dry with compressed air.
I Luoricate att the pans with oil before reassembly.
NOTE:
. This transmission uses no gaskets between the majorhousings; use liquid gasket (P/N 08718-0001 or08718-0003)
(see page '13-93).
. Always clean the magnet @ whenever the transmission housing is disassembled.
. Inspect all the bearings for wear and operation.
?-c
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13-54

Mainshaft Thrust Clearance
Adjustment
1. Remove the 72 mm thrust shim and oil guide platefrom the transmission housing.
4.
TFANSMISSIONHOUSING
72 mm THRUST SH|M
TRAt{SMtSStONHOUSINGOIL GUIOE PLATE
lnstall the 3rd/4th synchro hub. spacer collar,5thsynchro hub. spacer, and ball bearing on the main_shaft, then install the above assembly in the trans_mission housing.
lnstall the washe[ on the mainshaft,
Measure distance @ between the end of the trans-mission housing and washer.
NOTE;
. Use a straight edge and vernier caliper.. Measure at three locations and average the read_ing.ENO otlnA sMtsstoNHOUSINGMAINSHAFT
3RD/irTH SYNCHRO HUB
SPACCR COLLAR
5TH SYNCHRO HUB
o
B
13-88
AALL BEARING
V.
5. Measure distance @ between the end of the clutchhousing and bearing inner race.
NOTE;
. Use a straight edge and depth gauge.. Measure at three locations and average the read-ings.
Select the prcpet 72 mm thrust shim from the chartby using the formula below.
NOTE: Us€ only one 72 mm thrust sntm.
Shim Selection Formula:
From the measurements you made in steps 4 and 5:. Add distance O lstep 5) to distance @ (step 4).
. From this number, subtract 0.93 (which is themidpoint of the flex range of the clutch housingbearing spring washer).
. Take this number and compare it to the availableshim sizes in the chart.
{For example)
B;2.39
+ C: 0.22- 0.93
2.61 = 1.68
Try the 1.68 mm (0.0661 in) shim.
INNER RACE ot EALL BEARING

Automatic Transmission
Special Tools ......... .....'."".'-.-.' 14'2
Description .,....................-...... 14-3
power Flow ......,................. 14"6
Elestronic Control System .... . ................'..'.'.. 14-13
Hvdraulic Control .....'......" 1'l-19
Hydraulic F|ow...... .'.'.".'....11-21
Lock-up System '............ ... t/t'33
Electrical System
Component Locations....,.............'......'.............'.,. 14'39
PCM Circuit Diagram
lA/T Control Syst€m: '96 - 98 Models) .........'.. 1/t-40
PCM Tarminal Volt8ge/Measuring Condhions
{'96 - 98 ModeblA/T Control System ............
PCM Circuit Disgram(A/T Conlrol System: '99 - 00 Modsls) '..........' 14-44
PCM Terminal Voltage/Measuring Conditions('99 - 00 Models)A/T Control System ...
Troubleshooting Proceduros ....
Symptom-to-ComPonent Chari
Efectricaf SFiem - '96 - 98 Models '..-.-..."'.'..11-52
Eloqtrical System -'99 - 00 Modols ... .........". 1+54
EleclricatTroubl$hooting ('96 - 98 Models)
Valve Body
Repair .................... ........'.... 14-139
Valve
Assembly
ATF Pump
1,1-1i10
Inspection ...........'.......... 14-141
Main Valvs Body
Disass€mbf y/lnspoction/R.sssembly .'.'.'.'.. -. -. 1 1-1 12
Secondsry Valve BodY
Disa$embfy/lnspoction/Rsassembly ......'.'.'.'. 11-111
Regulator Valve Body
Disa$embly/lnspoction/Rea3sembly ..........'... 14-1{5
Servo Body
Disassombly/lnsp€ction/Reassembly .".'........ 14-146
Lock-up Valv6 Body
Dis$s.mbf y/ln3poction/Rea$embly .'.. -. -..'.'.' 1 1-1 17
Mainsh!ft
Dkassembly/lnep€ction Reassembly ..'...'........ 14'148
Inspoction .............'..........'. l it-149
Countsrshaft
Disa$embly/lnspeqtion/Rea3sembly .......'...'.. 1a-l51
Dba$ombly/Re$s.mblY11-152
til-46
I rl-48
Troubleshooting Flowcharts
Electrical Troubleshooting ('9!t - 00 Models)
Troublsshooting Flowchart3
Lock-up Control Solenoid vslvo A/B AssemblY
RePlacoment
Shift Cont.ol Solenoid Valve A/B A3sembly
Inspestion
Ona-way Clutch
Disassembh/lrupoction/Rca$embly .. "'........ l4-155
Clutch
lllustlttcd Ind.x {A48A, B4RA Transmlssion) ..' 14-156
tustr.tod Index (MrnA Transmi$ionl ............ til-158
...................... 14-153
L
14-56
1+81'
14-105
1+105
Replacoment ......
Mainshaft/Countorshaft Spo€d Sonsors
Replacemsnt ......'."'........... lit'108
Hydraulic System
Symptom-to-Componeni Chart
Hydraulic Sydemr+109
t4-113
1+116
11-117
Rea$emblY
14-106 Difforrr ial
llhdraied Index........ t4-156
B.ckhrh ln3poction. 14-167
Boaring Roplacemont..-..........11-167
..... 14-108 Diftrrsniial Carrior Repl8cemeni .'.-.............'...' lil-168
Oil Sall Romovalt4-t 59
Oil Soal ln3tallstion/Sidc Clearance'......'.....'... 1'l'169
Torqua Convertcr Housing Boarings
Mlin3haft Besring/Oil Scal Roplac.ment ."..'.. lil-172
Counio6hatt Betring R.plscem.nt ..'...... ....... 14-173
Test.....,......14-106
14-107
14-160
11-162
11-171
11-175
Replacement
Test .....,.,..........
Road Te3t
Linear Solenoid AsssmblY
Stall Speed
lllustrated Indax
Transmission/End Cover'. ....
Transmission Hou3ing,.............'.'......'....""..-.-.. 11-128
Torque Conve.ter Housing/Valvo Body ........... 14-130
End Cover
14-itB Park Stop
1+119 In3pection/Adiustmsnt...'......'.'............'...."""'14-175
Transmbgion
Reassombly
11-122 Torquo Convertet/Drivr Plsie ............'.'............'.. . l4-182
Transmission
11.726 Inrtallation
Tranlmission Housing Boarings
Msinsh.ft /CounteEhaft Bearings
B!pltcomgnt
Rcvo.3s ldlor Gear
lnrtallation
Cooler Flushing ..
Shift Cabls
Test
Fluid Level
Checkin9 .........."..'.'.....
Changing
Pressure Testing
Transmission
Transmission
Rgmoval ..
lil-176
.'..........'.'.'..... 1'l-183
.... lil-187
11-132Adiustmont
RemovaUlnttallation1,1-190
lit-191Transmisgion Housing
Removal ... '.'...... ......'..... 14-l3il
Tolque Convgrter Housing/valvs Body
Rsmoval .........,...... ............. 14-136
Valve CaDs
Description .......'................. t 4'138
Shift lndicator Panel
Adiu3tmant ..'.................. 14-192
ATF Coolor Hoses
Connection ..,............,.,....... l'l-192
Shift Lever .,........

Description
The automatic transmission is a 3-element torque converter and a dual-shaft electronically controlled unit which provides
4 soeeds forward and 1 reverse.
Torque Convertel, Geats, and Clutches
The torque converter consists of a pump, turbine and stator, assembled in a single unit. They are connected to the engine
crankshaft so they turn together as a unit as the engine turns. Around the outside of the torque converter is a ring gear
which meshes with the starter pinion when the engine is being started. The entire torque converter assembly seryes as a
flywheel while transmiuing power to the transmission mainshaft.
The transmission has two parallel shafts: the mainshaft and the countershaft. The mainshaft is in Iine with the engine
crankshaft. The mainshaft includes the 1st, 2nd and 4th clutches, gears tor 2nd, 4th, reverse and lst (3rd gear is integral
with the mainshaft, while the reverse gear is integral with the 4th gear). The countershaft includes the 3rd clutch, and
gears for 3rd,2nd, 4th, reverse. 1st and park. The gears on the mainshaft are in constant mesh with those on the counter-
shaft. When certain combinations of gears in transmission are engaged by clutches. power is transmitted from the main-
shaft to the countershaft to provide E, ld, E, and E positions.
Electronic Control
The electronic control svstem consists of the Powertrain Control Module {PCM), sensors, a linear solenoid and four
solenojd valves. Shifting and lock-up are electronically controlled for comtonable driving under all conditions. The PCM is
located below the dashboard, under the front lower panel on the passenger's side
Hydraulic Control
The valve bodies include the main vatve body, the secondary valve body, the regulator valve body, the servo body and the
lock-up valve body through the respective separator plates, They are bolted on the torque converter housang
The main valve body contains the manual valve, the 1-2 shift valve. the 2nd orifice control valve, the CPB {Clutch Pressure
Back-up) valve, the modulator valve. the servo control valve, the relief valve, and ATF pump gears The secondary valve
body contains the 2-3 shift valve. the 3-4 shift valve, the 3-4 orifice control valve, the 4th exhaust valve and the CPC (Clutch
pressure Control) valve. The regulator valve body contains the pressure regulator valve, the torque converter check valve,
the cooler relief valve, and the lock-up control valve. The servo body contains the servo valve which is integrated with the
reverse shift fork, and the accumulators. The lock-up valve body contains the lock-up shift valve and the lock-up timing
valve. The linear solenoid and the shift control solenoid valve Ay'B are bolted on the outside of the transmission housing,
and the lock-up control solenoid valve Ay'B is bolted on the outside of the torque converter housing. Fluid from regulator
passes through the manual valve to the various control valves. The clutches receive fluid from their respective teed pipes
or internal hydraulic circuit.
Shift Control Mechanism
Input from various sensors located throughout the car determines which shift control solenoid valve the PCM will activate
Activating a shift control solenoid valve changes modulator pressure, causing a shift valve to move. This pressurizes a line
to one of the clutches, engaging that clutch and its corresponding gear, The shift control solenoid valves A and B are con-
trolled by the PCM.
Lock-up Mechanism
In ,Dt1 position, in 3rd and 4th. and in E position in 3rd, pressurized fluid is drained from the back of the torque converter
through a fluid passage, causing the lock-up piston to be held against the torque converter cover. As this takes place, the
mainshaft rotates at the same as the engine crankshaft. Together with hydraulic control, the PCM optimizes the timing of
the lock-up mechanism. The lock-up valves control the range of lock-up according to lock-up control solenoid valves A and
B, and linear solenoid. When lock-up control solenoid valves A and B activate, the modulator pressure changes The lock-
up control solenoid valves A and B and the linear solenoid are controlled by the PCM.
(cont'd)
14-3

Description
(cont'dl
Gear Selection
The shift lever has six positions: E PARK. E REVERSE, N NEUTRAL, E 1st through 4th gear ranges, E 1st through 3rdgear ranges, @ 2nd gear.
Starting is possible only in E and E positions through the use of a slide-type, neutral-safety switch.
Automatic Transaxle (A/f, Gear Position Indicator
The Ay'T gear position indicator in the instrument panel shows which gear has been selected without having to look downat the console.
Clutch€s
The four-speed automatic transmission uses hydraulically-actuated clutches to engage or disengage the transmission gears.When hydraulic pressure is introduced into the clutch drum, the clutch piston moves. This presses the friction discs andsteel plates together, locking them so they don't slip. Power is then transmitted through the engaged clutch pack to itshub-mounted gear. Likewise, when the hydraulic pressure is bled from the clutch pack, the piston releases the friction discsand the steel plates, and they are free to slide past each other. This allows the gear to spin independently on its shaft,transmitting no power.
lst Clutch
The 1st clutch engages/disengages 1st gear, and is located at the end of the mainshaft, just behind the right sroe cover.The 1st clutch is supplied hydraulic pressure by its ATF feed pipe within the mainshaft.
2nd Clulch
The 2nd clutch engagegdisengages 2nd gear, and is located at the middle of the mainshaft. The 2nd clutch is joined
back-to-back to the 4th clutch. The 2nd clutch is supplied hydraulic pressure through the mainshaft by a circutr connect-ed to the internal hvdraulic circuit,
3rd Clutch
The 3rd clutch engages/disengages 3rd gear, and is located at the end of the countershaft. The 3rd clutch is suooliedhydraulic pressure by its ATF feed pipe within the countershaft.
ilth Clutch
The 4th clutch engages/disengages 4th gear, as well as reverse gear, and is located at the middle of the mainshaft. The4th clutch is joined back-to-back to the 2nd clutch. The 4th clutch is supplied hydraulic pressure by its ATF feed pipewith in the mainshaft.
\-a
PositionDe3cription
E PARK
E REVERSE
N NEUTRAL
E DRIVE
{1st through 4th)
Ei DRtvE('lst through 3rd)
B SECOND
Front wheels locked; park pawl engaged with pa* on countershaft. All clutches released.
Reverse; reverse selector engaged with countershaft reverse gear and 4th clutch locked.
All clutches released.
General driving; starts off in 1st, shifts automatically to 2nd, 3rd, then 4th, depending on vehiclespeed and throttle position. Downshift through 3rd, 2nd and 1st on deceleration to stop. The lock-upmechanism comes into operation in @ position in 3rd and 4th gear.
Use for rapid acceleration at highway speeds and general driving; up-hill and down,hill dfiving; stansotf in 1st, shifts automatically to 2nd, then 3rd, depending on vehicle speed and throttle position.
Downshifts through 2nd to lst on deceleration to stop. The lock-up mechanism comes into operationin 3rd gear,
Use for engine braking or better traction starting off on loose or slippery surfaces; stays in 2ndgear, does not shift up and down.
14-4

\
@ Position
As the engine turns, the ATF pump also starts to operate, Automatic transmission fluid (ATF) is drawn from (99) and dis-
charged into (1). Then, ATF flowing from the ATF pump becomes the line pressure (1). The line pressure (1) is regulated
by the regulator valve. The torque conv€rter inlet pressure (92) enters (94) of the torque converter through the lock-up
shift valve and discharges into (901. The torque converter ch€ck valve prevents the torque converter pressure from rising'
Under this condition, the hydraulic pressure is not applied to the clutches'
NOTE: When used, "1eft" or "right" indicates direction on the hydraulic circuit'
14-25