1998 HONDA CR-V ESP

ldle Control System
ldle Air Control llAC) Valve
The scan tool indicates Diagnostic Trouble Code (DTC) Pl508: A probtem in the ldle Air Controt flAC) varvecircuit.
The IAC Valve changes the amount of air bypassing the throttle body in response to a current signal from the ECM/PCM inorder to maintain the proper idle speed.
37 model;
IAC VALVE 2P CONNECTOR {C132}
,f rcp'# IYEL/BI.(II2f-1-d)
Y
Wir€ side of female terminals
PCM CONNECTOR A I32PI
tacvIBLK/BLU)
From AIR To INTAKECLEANER MANIFOLD
Wire side of female terminals
The MIL has beon .eport€d on.OIC Pl508 is sto.ed.
Problem veiification:1. Do the PCM Reset Procedure.2. Start the engine, and warm itup to normal operating tem-perature.
Inte.mittent failure, systcm b OKat thi3 time. Check tor poo. con-nections or loose wircs at C132(lAC v.lvel and at the PCM.
ls DTC Pl508 indicated?
Check lor an open in the wir6{lGPl lins}:1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector.3. Turn the ignition switch ON {ll).4. Measure voltage between bodyground and the IAC valve 2Pconnector term inal No.2.
Repair open in the wire trctwoontha IAC v!lv6 and the PGM-Flmain relly.
Chock for an opan o. short in thowi.e (lACv linel:1. Turn the ignition switch OFFand reconnect the IAC valve2P connector.2. Disconnect the PCM conneclorA (32P).
3. Turn the ignition switch ON {ll).4, Measure voltage betweenbody ground and PCM con-nector terminal A12.
{To page 1l-153)
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Description
General Operation
The Automatic transmission is a 3-element torque converter and triple-shaft electronically controlled unit which provides 4
speeds forward and 1 reverse speed The unit is positioned in line with the engine'
There are two tvoes of automatic transmission on CR-V; the four-wheel drive (4WD) model ('97 - 00)' and the front-wheel
drive (2WD) model ('98 - 00).
Toroue Converter, G€ars, and Clutches
The torque converter consists of a pump. turbine. and stator assembly in a single unit. The torque converter is connected to
the engine crankshatt. These parts 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 started. The torque converter assembly serves as a fly-
wheel while transmitting power to the transmission mainshaft.
The transmission has three parallel shafts: the mainshaft. the countershaft, and the sub-shaft. The mainshaft is in line with
the engine crankshaft. The mainshaft includes the 1st, 2nd. and 4th clutches, and gears lor 3rd,2nd,4th. reverse and 1st
(3rd gear is integral with the mainshaft, while reverse gear is integral with the 4th gear). The countershaft includes the 3rd
clutch and gears for 3rd,2nd, 4th, reverse, 1st, and park. Reverse and 4th gears can be locked to the countershaft at its cen-
ter, providing 4th gear or reverse, depending on which way the selector is moved. The sub-shaft includes the lst-hold
clutch and gears for lst and 4th.
The gears on the mainshaft are in constant mesh with those on the countershaft and sub-shaft. When certain combinations
of gears are engaged by the ctutches, power is transmitted from the mainshaft to the countershaft to provide E, D!, tr, tr,
and E position ('97 - 98 models). and E. E, E, and E position ('99 - 00 models)'
Electlonic Control
The electronic controt system consists of the Powenrain Control Module (PCM), sensors, a linear solenoid, and four
solenoid valves. Shifting and lock-up are electronically controlled for comfortable driving under all conditions. The PCM is
located below the dashboard, under the kick panel on the passenger's side.
Hydraulic Control
The valve bodies include the main valve body, the secondary valve body, the regulator valve body, the servo body, and
the lock up valve body. They are bolted to the torque converter housing. 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
bodv contains the pressure regulator valve, the torque converter check valve, the cooler relief valve, and the lock-up con-
trol valve. The servo body contains the servo valve which is integrated with the reverse shift tork, 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 con-
trol solenoid valve Ay'B are bolted to the outside of the transmission housing, and the lock-up control solenoid valve Ay'B is
bolted to the outside of the torque converter housing. Fluid trom the regulator passes through the manual valve to the
various control valves. The clutches receive fluid from their respective feed pipes or internal hydraulic circuit
ShiftControl Mechanism
input from various sensors located throughout the vehicle determines which shift control solenoid valve the PCM will acti-
vate. 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
controlled by the PCM.
Lock-up Mechanism
tn E! position (,97 - 98 modets) and in E position ('99 - O0 models), in 3rd and 4th, and in Del position in 3rd ('97 - 98
models) and in El position with Over,Drive (O/D) is OFF (by pressing rhe O/D switchl in 3rd ('99 - 00 models), 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 speed 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 the 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
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3rd Clutch
The 3rd clutch engages/disengages 3rd gear, and is located at the end of the countershaft, opposite the end cover. The 3rd
clutch is supplied hydraulic 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. The 4th
clutch is joined back-to-back to the 2nd clutch. The 4th clutch is supplied hydraulic pressure by its ATF feed pipe within the
mainshaft.
One-way Clutch
The one-way clutch is positioned between the park gear and the countershaft 1st gear, with the park gear splined to the counter-
shaft. The countershaft 1st gear provides the outer race surface, and the park gear provides the inner race surface The
one,way clutch locks up when power is transmitted from the mainshaft lst gear to the countershaft 1st gear. The 1st
clutch and gears remain engaged in the 1st, 2nd, 3rd, and 4th gear ranges in the lo], pt, E, or E position The one-way
clutch disengages when the 2nd, 3rd, or 4th clutches/gears are applied in the lor, [d, E, or E position'
This is because the increased rotational speed of the gears on the countershaft over-ride the locking "speed range" of the
one-wav clutch. The one-wav clutch free-wheels when the lst clutch is engaged
lST.HOLDCLUTCH
1ST CLUTCH
MAINSHAFT3RD CLUTCH
COUNTERSHAFT
TRANSFERSHAFT DRIVEGEAR
TRANSFERASSEMBLY
NOTE: The illustration shows the 4WD
automatic transmission {sectional view)
the 2WD transmission does not have a
transfer assembly and transfer shaft drive
gear on the differential assembly.
2NO CLUTCH4TH CLUTCH
INSIDE OF ONE.WAYCLUTCH
ONE.WAY CLUTCH
OUTSIDE OF ONE.WAYCLUTCH
The sprags engage/disengage outsideand inside of theSplined with counter- -
shaft
OVER.RIOINGLOCKING SPEED CONOITIONLOCKING CONDITION
14-5,
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Ascending Control {37 Modol}
When the PCM determines that the vehicle is climbing a hill in E] and E positions, the system extends the engagement
area of 2nd g€ar and 3rd gear to prevent the transmission from frequently shifting between 2nd and 3rd gears, and
between 3rd and 4th gears, so the vehicle can run smooth and have more power when needed.
NOTE:
. Shift schedules stored in ths PCM between 2nd and 3rd gears, and between 3rd and 4th gears. enable the PCM's fuzzy
logic to automatically select the most suitable gear according to the magnitude of 8 gradient.
t Fuzzy logic is a form of artificial intslligence that lets computers respond to changing conditions much like a human
mind would.
3RD - tlTHASCENoING MODE: UFhift Sch.dulc
- . FLAT ROAD MODE
-----------. : GRADUAL ASCENDING MODE
- - - - - : STEEPASCENDING MODEo5l)
FFN1NS
7,.,.7a
: 2ND-3RD SHIFTING CHARACTERISTICSCONTROL AREA| 3RD-aTH SHIFTING CHARACTER|SnCSCONTROL AREA
62 mph
1100 km/h)Vehicle .o..d
Asconding Conirol ('98 - 00 Mod.ls)
When the PCM determines that the vohicle is climbing a hill in E] and E positions ('98 model), and in E] position ('99 -
00 models), the system extends the engagement srea of 2nd gear and 3rd gear to prevent the transmission from frequent-
ly shifting between 2nd and 3rd gears, and between 3rd and 4th gears, so the vehicle can run smooth and have more
power when needed.
NOTE: Shift schedulss stored in the PCM between 2nd and 3rd gears, and between 3rd and 4th gears, enable to selsct the
most suitable gear according to th6 magnitude of a gradi€nt.
ASCENDING MODE: Up.hift Sch.dul.
NN : 2ND-3RD SXImNG CHARACTERISTICS- GoNTRoLAREA
VVVVVZ:IRD-ITHSHIFnNGCHARACTERISTICS- cot{TRoL AREA
850
o
6:l mph11fl) km/hl
(cont'd)
2ND - 3RD
2ND + 3RD 3RD + 4TH
Vahicl. sDctd
14-19
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Symptom-to-Component Chart
Hydraulic System (cont'd)
SYMPTOMCheck these items on thePROBABLE CAUSE ListCheck these items onthe NOTES Lisr
Shift lever does not operate smoothly.o, JdPFails to shift; stuck in 4th gear.14, 41 , 48
Transmission will not shift into park in E position.6, 38, 61PStall rpm high; all clutch pressures are in specification.40D,K,OLock-up clutch does not disengage.18, 43, 44, 45, 46, 49,50,57
Lock-up clutch does not operate smoothly.14, 40, 43, 44, 45, 46, 49, 50. 57Lock-up clutch does not engage.'t8, 40, 43, 44, 45, 46, 49, 50, 56, 57Vibration in all positions.
No engine braking in I position.59
Shift position indicator does not indicate anv position,6. 38, 60
PROBABLE CAUSE
I 33 Thrust washer worn/damaged
ATF pump worn or binding34Clutch clearance incorrect
Regulator valve stuck or regulator valvespflng wornDrive plate delective or transmission mtsas-sembled
Servo valve stuck5ttTorque converter housing or transmissionhousing bearing worn/damagedMainshaft worn/damaged
Shift cable broken/out of adjustmentATF strainer clogged
7Final gears worn/damaged38Shift cable is worn where it attaches to thetransmission or at the body mountsIOne-way (sprag) clutch worn/damaged
1st gears worn/damaged {2 gears)39Modulator valve stuck10lst clutch defective40Torque converter check valve stuck112nd gears worn/damaged (2 gears)41Foreign material in separator plate't22nd clutch defectiveCPB valve stuck
t53rd clutch defective43Lock-up timing valve stuck144th clutch defective44Lock-up shift valve stucktcReverse gears worn/damaged (3 gears)Lock-up control valve stuck16Excessive ATF46Lock-up clutch Diston defective17Torque converter one-way clutch defective47Shift control solenoid valve A defecttve
18Linear solenoid assemblv defective (,98 - OOmodels)48Shift control solenoid valve B dsfectrve
49Lock-up control solenoid valve A defective'19CPC valve stuckLock-up control solenoid valve B deleqtve20l-2 shift valve stuck51Servo control valve stuck212-3 shift valve stuck52lst accumulator defective3-4 shift valve stuck53Foreign material in 2nd exhaust orifice2nd accumulator defective54Foreign material in 3rd exhaust orifice3rd accumulator defectiveForeign material in 4th exhaust orifice4th accumulator defective56Mainshaft speed sensor defective262nd orifice control valve stuckCountershaft speed sensor defective273-4 orifice control valve stuck583rd sub accumulator defective2aForeign material in main orifice59lst-hold clutch defective29Foreign material in lst orifice60A/T gear position switch defective or out ofadjustment30Foreign material in reverse orifice
31Engine output low61Park gear mechanism defective32Needle bearing worn/damaged
14-154
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Differential
Differential Carrier Replacement
NOTE: The illustration shows the 4WD automatic trans-mission differential; the 2WD differential is similar.
1. Remove the snap ring from the differential carrier.
Remove the 5 x 15 mm roller (4WD) or 5 x 10 mmroller (2WDl and the speedometer drive gear.
SPEEDOMETER DRIVE GEAR RoI I FP
Remove the bolts securing the final driven gear andthe transfer shaft drive gear (4WD), then replace thedifferential carrier.
5 x 15 mm (/tWD)5 x 10 mm {2WDl
14-224
SPRING PINGROOVE
Install the final driven gear on a new differential car-rier with its chamfered side facing the carrier andthe transfer drive gear (4WD),
Tighten the bolts to the specified torque.
NOTE: The 2WD differentiat bolt has left-handthreads,
10 x 1.0 mm103 N.m 110.5 kd.m,7s.9 rbr.ft)
7.
FINAL DRIVEN GEAR
TRANSFER SHAFT
Install the speedometer drive gear with its cham-fered side facing the carrier. Align the cutout on thebore of the speedometer drive gear with the 5 x 15mm roller (4WD) or 5 x 10 mm roller (2WD).
Align the hooked end of the snap ring with thespring pin in the pinion shaft. then install the snaoring in the differential carrier groove
SNAP RINGInstall in this direction.Hooked end
PINION SHAFT
{4WDl
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Power Steering Hoses, Lines
Fluid Leakage Inspection
HOSES and LINES
. lnspect hoses for damage. leaks. interference and twisting
. Inspect fluid linesfor damage, rusting and leakage.
. Check for leaks at hose and line joints and connections.
FEED HOSE37 N.m 13.8 kgf.m, 27 lbtft)RETURN LINE JOINT28 N.m (2.9 kgf.m.21 lbf.ftl
CYLINDER LINES17 N.m (1.7 kgf.m. 12 lbf.ftl
FOWER STEERING PRESSURE SWITCH12 N.m (1.2 kgf.m,8.7 lbtft)
26 N.m (2.7 kgf.m, 20 lbf.ft)
GEARBOX .nd VALVE BODY UNllCheck for leaks at the mating surfaceand flare nut connections.
CYLINDER
FEED HOSE11 N.m('1.1 kgt.m, 8 lbf.ftl
SUCTION HOSE
PUMP ASSEMBLYCheck for leaks atthe pump
seal. inlet and outlet fittings.
Note these items during installation:
. Connect each hose to the corresponding line securely
until it contacts the stop on the line. Install the clamp
or adjustable clamp at the specified distance from the
hose end as shown.
. Check all clamDs for deterioration or deformation;
replace with the clamps new ones if necessary.
. Add the recommended power steering fluid to the
specified level on the reservoir and check for leaks.
ADJUSTABLE HOSE CLAMP: la)
. Position the adjustable hose clamps at the points
indicated by (a) in the drawing above.
. Slide the hose over the line until it contacts the stop.
HOSE CLAMP: lbl
. Position the hose clamps at the
(b) in the drawing above.
. Slide the hose over the line until
Replacement
10.01 - 0.22 in)
points indicatsd by
it contacts the stop,
2.0 - 4.0 mm10.08 - 0.16 inl2.5 - 5.5 mm{0.01 - 0.22 in}17 -23
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5. Submerge the valve in a container of power steer-
ing fluid or solvent, and blow in the hose. lf air bub-
bles leak through the valve at less than 98 kPa
(1.0 kgflcm', 14.2 psi), repair it as follows ('97 model).
For'98 - 00 models, the flow control valve cannot
be disassembled; replace the pump as an assembly
AIR PRESSURE
POWER STEENINGFLUID or SOLVENT
6.For'97 model only, hold the bottom end of the
valve with a open end wrench. Unscrew the seat in
the top end of the valve, and remove any shims, the
reliel check ball, relief valve and relief valve spring.
RELIEFALVE
RELIEF CHECK BALL
{w@r
7.
SEAT9 N.m(0.9 kgf.m, 6.5 lbfft)
RELIEF VALVESPRING
FLOW CONTBOL VALVE
Clean all the parts in solvent, dry them otf, then
reassemble and retest the valve.
The relief pressure is adjusted at the factory by
adding shims under the check ball seat lf you found
shims in your valve, be sure you reinstall as many
as you took out.
lf the flow control valve tests OK, reinstall it in the
pump. It the flow control valve still leaks air, replace
the pump as an assembly. The flow control valve is
not available separately.
8,
Hold this end witha open eno wrencn.
Ball Bearing:
'1. Inspect the ball bearing by rotating the outer race
slowly. lf any play or roughness is felt, replace the
ball bearing.
2. Replace the ball bearing using a press.
Removelnstall
Press
I
Press
I
lnstall with thered shaelded sidefacing down.
NOTEr SuPPort the inner race
with the tool securelY-
BALL EEARING
17-27
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