Control unit HONDA CIVIC 1997 6.G User Guide

Troubleshooting
Engine/P_o,wertrain Control Module Terminal Arrangement('99 - 00 Models except Dl6Y5 engine with M/Tl
ECM/PCM CONNECTOR A (32P)Wire side ot temale terminalsNOTE:Standard battery voltage is l2 V
ECM/PCM CONNECTOR A I32PI
Sign!l
3BLU2WSS (EVAP 8YPAsS SOLENOIDDrives EVAP bypass solenoid vatve,With gn'tion swnch ON (lll banery votlage
LT GRN/I/VIITVSV {EVAP CONTNOL CANISTERVENTSHUTVALVE]Drives EVAP controt ca n isrer v€nt shutWilh ignilion switch ON {tl): b€ttery vottage
8LU/GNNC8S (CRUISE CONTSOL SIGOown shift signal inpot lrom c.uise conrrolWhen crurss control is used:purses
68ED/YELPCS {EVAP PURGE CONTROLSOTENOIOVALVE)Drives EVAP purge conrrol sotenoid vatve.With engine running, engine cootant, betow r54.F (6a,C):
With engine.unning, €ngine coolant, abov€ 154.F(68'C): duty conlrolled
YELATPD {AT GEAR POSITIONSWITCH)ootects A/T gear posnion swilch s,gnar.In otherthan @ posilion: Apprcx. 5 V
8BLK,IflHTSO2SHTC (SECONDARY HEATED OXYGEN SENSOS HEATEFCONTFOL)
Drives sscondary h€ared oxygen senso.Wilh isn,rion swirch ON (ll):banery votraseWith lully warm6d dp€ngire runn'ng:dury controled
LT GRNATPNP (AT GEAF POSITIONSWITCH)oereds A/T 9€a r position switch signat.In Parr or neulrsl:0 VIn anyother position approx.5 v
t088NSCS (SERVICE CHECK SIGNAL)Oetects ssruice check connecror signal(the signalcausing a OTC indication)with rh€ t6rminal connected: 0 vWith the rerm ina I disconneded: abour 5 V of ban€ry
GNN/BIKD4IND (D4INDICATON]Drives Oa indicaio. lighr.With D4 indicator lightturned ON: O VWith D4 indicator lightturned OFF: battery vo ttageG8N/YETFTF (FUEL PUI\,4P SELAY)Orivos tuel pump relay,0V for two s€conds lfrer turnrng rgnilior swtcn ON(ll), then batt€ry voltage11BTI(REDACC (Al/C CTUTCH SELAY)Drives A./C clutch reray.With compressor ON:O VWilh comp.ssor OFF; battery vottage18GFN/OFNMI! (A,IAIFUNCTION INDICA.TOF LIGHT)With MlLturned ON:0 VWith l\,llL tornod OFF|batrery votrsge198tuNEP (ENGINE SPEED PUTSEIOulputs6ngine speed pulse,Wilh engin6.unning: putses
20GFNFANC {SADIATOR FAN CONTnoL)Orives radiarortan relay.Wirh r.distor t6n running:OVWith radiatortan stopped: banery vottage21ELUA/ELK LINESends and r€ceives s.an lool signal.With ignition switch ON (ll):p!ts€s
22'lBLUATP L {AT GEAS POSITIONswtTcH)Oelocis A"/T gear posirion switch siSnat.In othfflhan E position: Apprcx. 5 V
23SHO25 (SECONOARY HEATEDOXYCEN SENSOR, SENSOF 2)Detects secondsry hoar€d oxygen sensorWith lhronle f! lly or'6ned from idte with fu ywarmod up engine: above 0.6 vWiih th.onl6 quickb, closd:below 0,4 V24STS ISTAFTEN SWITCH SIGDebcrs staner switch signat.Wirh srarterswitch ON (tttJ: batteryvottogeWith sraftsr cwirch OFF:0 V26GFNPSPSW iPlS PNESSURESWITCII SIGNAL)Derecrs PSP switch signat.Atidle with steoring wheolin srraightahead position: O VAt idl6with steering wheetal fult lock: barery vo ttags27BLU/REOACS (AJC SWITCH SIGNALJOer*ts ,ay'C swirch signat.Wiih ty'C switch ON;0VWilh Ay'C switch OFF|aboor 5VWHT/REDSLU iINTERLOCK CONTROIUNIT)Drivos interloct control unit.With ignltion switch ON (ll)and brake pedaldepresed: batlory volrage29LT GRNPTANK (FUEL TANK PFESSUEESENSOR)Oer6ds lu€l tank pr€ssura sonsor signat.Wilh ig.rrrd swirch ON rttr and fuetti

cap ooen6d.
30GRN/FEOEr (ELOIWith parking lighlsrurned on ar idteiaboui 2.5- 3.S VWirh low beam he€dlig hts turnqd on ai idts: aboul 1.52.5 V32GRN/'WHTAKSW (BFAKE SWITCH)Detets brak€ swrtch signEt,With brake pedal r6l€ased:0 VWhh brake pedaldepres*d: battery voltEse'1:A./T (D16Y7, D16Y8 engine)*2: rvt/T13: CVT (D16Y5 engine)
11-92

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

Road Test
(cont'dl
.91 Position: Dl6Y7 engine
. Upshift
Throttle OpeningUnit of speedlst + znd2nd * 3rd3rd t 4thLock-up ON
Throttle position sensor
voltage: 0.75 V
mph9-1220-2328-3221 -24
km/h15-1932-3745-5234-39
Throttle position sensor
voltage:2.25 V
mph40-4562-67
km/h34-4095 - 10499 - 't08
Fully-opened throttle
Throttle position sensor
voltage: 4.5 V
mph33-38101 - 't1299 - 109
km/h53-61102-115163 - 180'159 - 176
Downshift
Throftle OpeningUnit of speedLock-up OFF'lth + 3rd3rd + 2nd2nd t lst
Fully closed throttle
Throttle position sensor
voltage: 0.5 V
mph't9 - 2217 -206-9(3rd+lst)
km/h30-3527 -3210 - 15 (3rd + 1st)
Fully-opened throttle
Throttle position sensor
voltage: 4.5 V
mpn95 - 10585-9554-6125-30
km/h153 - 169137 - 15387-9840-48
-q1 Position: DI6YB engine
. Upshift
Downshift
NOTE:
. Lock-up ON: The lock-up control solenoid valve A turns ON.. Lock-up OFF: The lock-up control solenoid valve A turns OFF.
Throttle OpeningUnit of speedlst + 2nd2nd - 3rd3rd + 4thLock-up ON
Throftle position sensor
voltage: 0.75 V
mph9-1220-232A-3221 -24
km/h15-1932-3745-5234-39
Throttle position sensor
voltage:2.25 V
mpn21 -2540-4559-65
km/h34-4095 - 10499 - 108
Fully-opened throttle
Throttle position sensor
voltage: 4.5 V
mph32-3762 -7096 - 10795 - 106
km/h52-60100 - 113't55 - 112't53 - '170
Throttle OpeningUnit ot speedLock-up OFF'lth + 3rd3rd+2nd I 2nd+lst
Fully-closed throttle
Throttle position sensor
voltage: 0.5 V
mph19-2217 -206-9(3rd+ 1st)
km/h30-3527 -32l0 - 15 (3rd + lst)
Fully opened throttle
Throttle position sensor
voltage: 4.5 V
mpn91 - 10154-61 25-30
km/h'147 - 163137 - 15387-98 I 40-48
l.
14-114

CHECK BALL
w
MAIN VALVE BODY(Sectional viewl
SPRING SPECIFICATIONS
CHECK BALLS
CHECK BALLS
Unit: mm (in)
No.Springs
Standard (New)
Wire Dia.o.D.Free LengthNo. ot Coils
o
@
@
@
@
@
Relief valve spring
Modulator valve spring
CPB valve spring
1-2 shift valve spring
2nd orifice control valve spring
Servo control valve spring
1.1 (0.043)'1.4 (0.055)
0.9 (0.035)
0.9 (0.035)
0.7 (0.028)
1.0 (0.039)
8.6 (0.342)
9.4 (0.374)
8.1 t0.3221
7.6 {0.302)
6.6 (0.262)
8.'t to.322l
37.1 (1.461)
35.0 (1.378)
47.2 (1.8s8)
41.3 (1.6261
34.8 (1.370)
52.1 t2.O51l
13.4
10.91C ?'15.3
22.0
20.8
1+143

Secondary Valve Body
Disassembly/lnspection/Reassembly
NOTE:
. Cleanall parts thoroughly in solvent or carburetor cleaner. and drywith compressed air, Blowoutall passages.
. Replace the secondary valve body kit. P/N 27700 - P4R - 315 (The secondary valve body kit includes the linear solenoid
assembly) if any parts are worn or damaged.
. Checkall valves for free movement. lf anyfailto slide freely, seeValveBody Repairon page 14-139,
. Coat all parts with ATF during assembly.
. The CPC valve is installed in the secondary valve body, held in place by the lock bolt.
2.3 SHIFT VALVE
3.4 SHIFT VAL
.TH EXHAUST VALVE
LOCK BOLTCAUTION: Do not move.
SECONDARY VALVE BODYInspect for wear, scratches 6ndscoring.
3-'l ORIFICE CONTROL VAL
VALVE
SPRING SPECIFICATIONSUnit: mm (in)
No.SpringsStandard {New)
Wire Dia.o.D.Free LongthNo. of Coils
ora,.n
3-4 shift valve spring
2-3 sh ift valve spring
4th exhaust valve spring
3-4 orifice control valve spring
0.910.035)
0.9 {0.035)
0.9 {0.035)
0.7 {0.028)
7.6 (0.302)
7.6 (0.302)
6.1 10.2421
6.6 (0.262)
57 .O 12.2441
57 .O 12.2441
36.4 (1.433)
37.5 (1.476)
26.8
26.8
24.6
14-144

Regulator Valve Body
Disassembly/lnspection/Reassembly
NOTE:
. cleanall parts thoroughly in solvent or carburetor cleaner, and drywith compressed air. Blowoutall passages
. Replace the valve body as an assembly if any parts are worn or damaged.
. check allvalves for free movement. lf anyfail toslidetreely, see valve Body Repairon page 1+139.
1. Hold the regulator spring cap in place while removing the stop bolt. once the stop bolt is removed. release the spring
cap slowly.
CAUTION: The regulator 3pring cap can pop out when the stop boh is removod'
2. Reassembly is the reverse order ofths disassembly procedure.
NOTE:
o Coat all parts with ATF during assembly.
. Align the hole in the regulator spring cap with the hole in the valve body, then press the spring cap into the valve
body, and tighten the stop bolt.
STOP BOLT6x1.0mm12 N.m 11.28.7 tbf.lrl
^/^'ou*'oRsPRrNGcAP
*N@
REGULATOR VALVE
\=f -.-*
*fi /F { a-tLocK.uPcoNrRoLvALVE
cooLERRELlEFvALVr"r?
ry
roRouE coNvERrER cHEcKv ^LvE//
v ^r* "r**::f vi{LvE cAp
SPRING SPECIFICANONS
REGULATOR VALVE BODY
Inspect lor wear, scratches
and scorlng.
Unit: mm (in)
No,Springe
Standard (Now)
Wire Dia.o.D.Free LengrthNo. of Coils
o
o
@
@
@
Regulator valve sPring A
Regulator valve spring B
Stator reaction spring
Cooler relief valve spring
Torque converter check valve spring
Lock-up control valve sPring
1.8 {0.07'r)
1.8 (0.071)
4.5 (0.177)
1.0 (0.039)
1.0 (0.039)
0.7 (0.028)
'r4.7 (0.584)
9.6 (0.381)
35.4 (1.407)
8.4 {0.334)
8.4 {0.334}
6.6 {0.262}
87.8 (3.457)
44.0 (1.732)
30.3 (1.193)
33.8 (1.331)
33.811.3311
38.0 {1.4961
11.0
1.9
8.2
a.2't 4.1
14-145

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
,!

System Description
Fluid Flow Diagram
The system is a compact rotary-valve-type power steering, connected to the steering gearbox. The fluid pressure is pro-
vided by a vane-type pump which is driven by the engine crank pulley. The amount of fluid and pressure is regulated by
the flow control valve built into the pump. The fluid pressure from the pump is delivered to the valve body unit around the
pinion of the steering gearbox. The valve inside the valve body unit controls the hydraulic pressure and changes the direc-
tion of the flow. The fluid then flows to the power cylinder. where rack thrust is generated. Fluid returning from the power
cylinder flows back to the reservoir, where the fluid is "filtered" and supplied to the pump again.
RESERVOIR
VALVE BOOY UNIT
SUB.VALVE
FLOW CONTROL VALVESTEERING GEARBOX
17-16

System Description
Steering Gearbox
The rack-and-pinion type steering gearbox has a valve body unit incorporated with the pinion to control the steering fluidpressure. Steering fluid from the pump is regulated by a rotary valve in the valve body unit and is sent through the cylin,der line to the power cylinder, where hydraulic pressure is applied. The steering fluid in the other side of the power cylin,der returns through the cylinder line and valve body unit to the reservoii.
VALVE EODY UNIT
CYLINDER LINE
To RESERVOm +-From PUMP -;
POWER CYLINDER
Valve Body Unit
Inside the valve body unit is the valve, which is coaxial with the pinion shaft, and controls the steering fluid pressure. Thevalve housing is connected with the fluid line from the pump, the return line to the reservoir, and the two cylinder linesfrom the respective power cylinder. The pinion shaft is double - structured with the input shaft connected to the piniongear, both of which are interconnected with the torsion bar.
The pin inserted in the valve and the pinion shaft groove engage; this allows the pinion shaft to rotate together with thevalve. Because of this construction, the difference in angle in the circumferential direction between the input shaft and thevalve becomes larger according to the torsional strength of the pinion or steering resistance. However, maximum torsionbetween the shafts is regulated by the engaged splines of the shafts at the pin engagement section to hold the torsion barwithin the set value,
This allows the steering system to function as an ordinary rack-and-pinion type steering if the steering fluid is not pressur-
ized because of a faulty pump,
VALVE
Difforence in angle botwoon theinput shaft and pinion shsft
PINION SHAFT
lo
INPUT SHAFT
-l
a
17-20
INPUT SHAFT

Troubleshooting
General Troubleshooting
Check the following before you begin:. Has the suspension been modified in a way that would affect steering?. Are tire sizes, tire variety and air pressure correct?. lsthe steering wheel original equipment or equivalent?. lsthe powersteering pump belt properlyadiusted?
. ls steeringfluid reservoirfilledto proper level?. ls the engine idle speed correct and steady?
Hard Steering (Check the powor assist. se€ page 17-3o. lfthe torce is over 29 N (3.0 kgf, 6.6lbo, Procede with this troubleshootinq.)
Abnormallluid pressure
{fluid pressureis too high)
Faulty valve body unit
Relief pres-sure too low
Abnormal
Faulty llow control valve(Replace the pump es anassembly)
Ch€ck the feed snd return circuit lin€s ano nosebetw6€n the gearbox and pump for clogging andd€lormation.
Normal line and hose
Check the pump fluid pressure(soe page 17-34).l/easure steady-state tluid pres-s!re while idling with the bothvalves tully open.It should be 1.500 kPa (15 kgf/cmr,213 psi) or below.
Normal
Check th€ flow control vslve (see page 17-42).. Chock the valvo lor smooth movement in the hous-ing.. Check the reliefvalve for leaks.
Check the pump fluid pressure
{see page 17-34).Measure pump relief pressurewhile idling with the pressure con-trol valve Iully closed.It should be 6,400 - 7,400 kPa (65 -
75 kgflcm,,920 - 1,070 psi)
Normal relisf pressure
17-22
Go to page 17-23Faulty pump assembly