1997 HONDA CR-V Egr

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
www.emanualpro.com

Description
Hydraulic Control (cont'd)
Servo Body
The servo body is located on the secondary valve body. The servo body contains the servo valve (which is integrated withthe reverse shift fork), and the accumulators.
2ND ACCUMULATOR
3RD SUBACCUMULATOR
SERVO BODY
1ST ACCUMULATOR
SERVO VALVE/SHIFTFORK SHAFT
14-28
www.emanualpro.com

Transmission
Cooler Flushing
@@ To prevent in;ury to face and eyos, atwayswear safety glasses ot a face shield when using thetlansmission flusher.
This procedure should be performed before reinstallingthe transmission.
2.
LCheck equipment for wear and cracks before using.Replace any worn or cracked components.
Using the measuring cup. fill the tank with 21 ounces{approximately 213 lull) ol biodegradable flushingfluid (J35944 - 20). Do not substitute with any otherfluid. Follow the handling procedure on the fluidcontaaner.
Secure the flusher filler cap, and pressurize theflusher with compressed air to 550 - 829 kpa (5.6 _
8.45 kgf/cm,, 80 - 120psi). The air line should beequipped with a water trap to ensure a dry air sys-tem.
Hang the flusher under the vehicle.
Attach the flusher discharge hose to the return lineof the transmission cooler using a clamp.
Connect the drain hose to the inlet line on the trans-mission cooler using a clamp.
IMPORTANT:
Securely clamp the opposite end ofthe drain hose to abucket or floor drain.
DISCHARGEHOSE
tAirlp Water
TnAI{SrfiSStoN coot"€RFLUSHER{Comm.rcidly.v.il.bt.lK.r -Moor. J38,t{15.Aor aquival.nt
5.
14-264
7. With the water and air valves off, attach the water andair supplies to the flusher. (Hot water if available.)
10.
8.
1'I.
Turn on the water valve for 1O seconds. lf waterdoes not flow through the cooler, it is completelyplugged, cannot be flushed, and must be replaced.
Depress the trigger to mix the flushing fluid into thewater flow. Use the wire clip to hold the trigger down.
While flushing with the water and flushing fluid fortwo minutes, turn the air valve on for five secondsevery 15 - 20 seconds to create a surging action.AIR PRESSURE: MAX 845 kpa (8.45 kgf/cmr, t20 psi)
Turn the water valve off. Release the trigger, thenreverse the hoses to the cooler so you can flush inthe opposite direction. Repeat steps 8 through 10.
Release the trigger, and rinse the cooler with wate.for one minute.
Turn the water valve off, and the water supply off.
Turn the air valve on for two minutes, or until nomoisture is visible leaving the drain hose. Residualmoisture in the cooler or lines can damage thetransmission.
Remove the flusher from the cooler line. Attach thedrain hose to a container.
Install the transmission, and leave the drain hoseattached to the cooler line.
12.
13.
14.
to.
www.emanualpro.com

Description
Rear Differential
Outline
The Real-time 4WD-Dual Pump System model has a hydraulic clutch and a differential mechanism in the rear differential
assembly. Under normal conditions, the vehicle is driven by the front wheels. However, depending on to the driving force
of the front wheels and the road conditions. the system instantly transmits appropriate driving force to the rear wheels
without requiring the driver to switch between 2WD (tront wheel drive) and 4WD (four wheel drive). The switching mecha-
nism between 2WD and 4WD is integrated into the rear differential assembly to make the system light and compact.
ln addition, the dual-pump system switches off the rear-wheel-drive force when braking in a forward gear. This allows the
braking system to work properly on models equipped with an Anti-lock Braking System (ABS).
Construction
The rear differential assembly consists of the torque control differential case assembly and the rear differential carrier
assembly. The torque control differential case assembly consists of the differential clutch assembly, the companion
flange, and the oil pump body assembly. The rear differential carrier assembly consists of the differential mechanism. The
differential drive and driven gears are hypoid gears.
The oil pump body assembly consists of the front oil pump, the rear oil pump, the hydraulic control mechanism, and the
clutch piston. The clutch piston has a disc spring that constantly provides the differential clutch assembly with a preset
torque to Drevent abnormal sound.
The clutch guide in the differential clutch assembly is connected to the propeller shaft via the companion flange, and it
receives the driving force lrom the transfer assembly. The clutch guide rotates the clutch plate and the front oil pump in
the oil pump body.
The clutch hub in the differential clutch assembly has a clutch disc that is splined with the hypoid drive pinion gear. The
hypoid drive gear drives the rear oil pump.
The front and rear oil pumps are trochoidal pumps. The rear oil pump capacity is 2.5 percent larger that the front oil pump
to handle the rotation difference between the front and rear wheels caused by worn front tires and tight corner braking.
The oil pumps are designed so the fluid intake works as a fluid discharge when the oil pumps rotate in reverse. Genuine
Honda CVT fluid is used instead of differential fluid.
Operation
When there is a difference in rotation speed between the front wheels (clutch guide) and rear wheels (hypoid driven gear),
hydraulic pressure from the front and rear oil pumps engages the differential clutch, and drive force from the transler
assembly is applied to the rear wheels.
The hydraulic pressure control mechanism in the oil pump body selects 4WD mode when the vehicle is started abruptly,
or when accelerating in a forward or reverse gear (causing rotation difference between the front and rear wheels). or
when braking in reverse gear {when decelerating). lt switches to 2WD mode when the vehicle is driven at a constant speed
in forwar! or reverse gear (when there is no rotation difference between the front and rear wheels), or when braking in a
fo rwa rd gear (when decelerating).
To protect the system, the differential clutch assembly is lubricated by hydraulic pressure generated by the oil pumps in
both 4WD and 2WD modes. Also, the thermal switch relieves the hydraulic pressure on the clutch piston and cancels 4WD
mode if the temDerature of the differential fluid rises above normal.
www.emanualpro.com

Real-time 4WD-Dual Pump System
Troubleshooting (Automatic Transmissionl
When starting and accelerating in forward gesrs {4WDmodel
1. Lift up the vehicle so all four wheels are off theground (see section 1).
2. Make a mark on either No.
shaft.
'I or No.2 propeller
PROPELLER SHAFT
Start the engine, and let it run until it warms up (the
radiator fan comes on at least twice).
With the engine at idle. shift to the E position.
Apply the parking brake firmly. and measure thetime it takes the propeller shaft to rotate 10 times.. lf the measured time is more than 10 seconds,
the 4WD system is normal.
. lf the time is less than 10 seconds, there is aproblem in 4WD system. Check the differential
fluid. lf the differential fluid is normal, replace
the torque control differential case kit.
15-10
When starting and accelerating in revGrsg gear {4WDmodel
1. Lift up the vehicle so all four wheels are off theground (see section 1).
Make a mark on either No.
shaft.
1 or No. 2 propeller
PROPELLER SHAFT
Start the engine. and let it run until it warms up (the
radiator fan comes on at least twicei.
With the engine at idle, shift to the E position.
Apply the parking brake firmly, and measure the
time it takes the proDeller shaft to rotate 10 times,. lf the measured time is more than 10 seconds,
the 4WD system js normal.. lf the time is less than 10 seconds, there is aproblem in 4WD system. Check the differential
fluid. lf the differential fluid is normal, reolace
the torque control differential case kit.
www.emanualpro.com

10. Set the double loop band onto the boot or dynamic
damper with the band end toward the front of the
vehicle.
11. Pull up the slack in the band by hand.
12. Make a mark on the band 10 - 14 mm (0.4 - 0.6 in)
from the clip.
OOUBLE LOOP BAND
CLIP
13.
'14.
Thread the free end of the band through the nose
section of a commercially available boot band tool(KD-3191 or equivalent). and into the slot on the
winding mandrel.
Place a wrench on the winding mandrel of the boot
band tool. and tighten the band until the marked
spot on the band meets the edge of the clip.
BOOT BAND TOOL(KD-3191
or equivalentlMark on band.
15.
WINDINGMANDREL
Lift up the boot band tool to bend the free end of
the band 90 degrees to the clip, Center-punch the
clip, then fold over the remaining tail onto the clip.
(cont'd)
16-1 1
HAMMER
www.emanualpro.com

13.
14.
Thread the free end of the band through the nose
section of a commerciallv available boot band tool(KD-3191 or equivalent), and into the slot on the
winding mandrel,
Place a wrench on the winding mandrel of the boot
band tool, and tighten the band until the marked
spot on the band meets the edge of the clip.
BOOT BAND TOOL(KD-3191
or equivalent)Mark on band.
WINDINGMANDREL
Lift up the boot band tool to bend the free end of
the band 90 degrees to the clip, Center-punch the
clip, then fold over the remaining tail onto the clip.
HAMMER
16. Unwind the boot band tool, and cut off the excess
free end of the band to leave a 5 - 10 mm (0.2 - 0.4
in) tail protruding from the clip.
5-10mm(0.2 - 0.4 in)
17. Bend the band end by tapping it down with a ham-
mer.
NOTE:
. Make sure the band does not move.
. Remove any grease remaining on the surrounding
surfaces.
(cont'd)
16-27
www.emanualpro.com

Pump noiseGrating nois€trom pump
Pump noise
Raftle or chattering
Check the fluid lev€1.lt low, fill the reservoir to theproper level. and check for leaks.Tighten or roplace as necessary,
Cavitation caused by air bubblesin the fluid.
Check for a crushed inlet hose ora loose hose clamp allowing airinto the suction side of the system. Check the reservoir forcracks. Tighten or replace as nec-
Check the drive shaft oil seal.
Pump noise up to 2 - 3 minutesafter starting in cold weather isnormal, Compare pump noise atoperatrng temperature to anothervehicle.
ll pump noise is abnormally loud,remove and inspect the pump forwear and damage (see page 17-251.
Tighten or replace the pulley.lI shaft is loose, replace thepump.
17-9
www.emanualpro.com