1986 TOYOTA CAMRY V20 differential

3. INSTALL LH BEARING RETAINER
(a) Install a new O±ring.
(b) Position the retainer by tapping it while holding the dif-
ferential case center with the retainer.
(c) Clean the threads of the bolts and case with white gas-
oline.
4. INSTALL RN SIDE BEARING CAP
Tighten the bolts evenly and gradually while turning
the ring gear.
Torque: 730 kg±cm (53 ft±Ib, 72 N±m)
(d) Coat the threads of the bolts with sealer.
Sealer: Part No. 08833±00070, THREE BOND 1324
or equivalent
(e) Temporarily tighten the bolts evenly and gradually while
turning the ring gear.
INSTALLATION OF DIFFERENTIAL
1. PLACE OUTER RACE AND SELECTED ADJUSTING
SHIM ONTO RH SIDE BEARING
2. PLACE DIFFERENTIAL CASE INTO CASE
Be sure to install the adjusting shim into place.
± AUTOMATIC TRANSAXLEInstallation of Component Parts (A140L and A1 40E)AT±162

DESCRIPTION
GENERAL
(A540E)
The A540E is a 4±speed, Electronic Controlled Transaxle (hereafter called ECT) developed exclusively for
use with a transversely±mounted engine. A lock±up is built into the torque converter.
The A540E transaxle is mainly composed of the torque converter, the 4±speed planetary gear unit, the
differential, the hydraulic control system and the electronic control system.
± AUTOMATIC TRANSAXLEDescription (A540E and A540H)AT±184

(A540H)
The A540H automatic transaxle design is based on the A540E automatic transaxle and equipped with
a center differential and transfer.
This transaxle has the same hydraulic multiplate clutch in the center differential limiting control mecha-
nism as the A241 H automatic transaxle on the Corolla All±TRAC/4WD Station Wagon. The fluid pres-
sure acting on the hydraulic multiplate clutch of the A540H is controlled by the ECT ECU (Electronic
Control Unit according to the vehicle driving conditions. As a result, torque is distributed to the front
and rear wheels appropriately at all times to maximize the overall performance of the 4WD vehicle.
NOTICE: Special handling methods are necessary for full±time 4WD vehicles during inspection and mainte-
nance. Instructions concerning these handling methods are given on page IN±8.
± AUTOMATIC TRANSAXLEDescription (A540E and A540H)AT±185

Throttle cable out of adjustment
Throttle cable and cam faulty
Accumulator pistons faulty
Valve body faulty
Transaxle faultyAdjust throttle cable
Inspect throttle cable and cam
Inspect accumulator pistons
Inspect valve body
Disassemble and inspect
transaxle
General Troubleshooting (Cont'd)
Inspect throttle cable
Inspect valve body
Disassemble and inspect
transaxle
Inspect solenoid valve
Inspect electronic control
Inspect electronic control
Inspect valve body
disassemble and inspect
transfer
Disassemble and inspect
center differential clutch Inspect solenoid valve
Inspect electronic control
Inspect valve body
Disassemble and inspect
transaxle Inspect electronic control
Inspect valve body
Inspect solenoid valve
Disassemble and inspect
transaxle
Solenoid valve faulty
Electronic control faulty
Valve body faulty
Transaxle faulty Electronic control faulty
Valve body faulty
Solenoid valve faulty
Transaxle faulty
Shift cable out of adjustment
Parking lock pawl and spring faultyInspect solenoid valve
Inspect electronic control
Inspect valve body Inspect valve body
Inspect solenoid valve
Inspect electronic control
Solenoid valve faulty
Electronic control faulty
Valve body faulty
Electronic control faulty
Valve body faulty
Transfer faulty Valve body faulty
Solenoid valve faulty
Electronic control faulty
Throttle cable faulty
Valve body faulty
Transaxle faulty
Solenoid valve faulty
Electronic control faulty Down±shift occurs too
quickly or too late while
coasting
Adjust shift cable
Inspect cam and spring No down±shift when
coasting
Hydraulic multiplate clutch faultyAT±218
AT±203
AT±308
AT±236 AT±203
AT±308
AT±218
AT±236
AT±219


 No engine braking in 2
or L range No lock±up in 2nd,
3rd or O/D
No center differential
Control No O/D±3, 3±2
or
2±1 kick±down

AT±219

Vehicle does not hold
in P rangeAT±308
AT±218
AT±203
AT±218
AT±203
AT±308 AT±201
AT±308
AT±236 AT±403
AT±308
AT±236
AT±203
AT±368
AT±343 AT±219


AT±219
 Harsh down±shift
AT±201
AT±392 AT±201
AT±201
AT±218
AT±203AT±219
 Possible cause
ProblemRemedy
AT±335 A540H
A540EPage
± AUTOMATIC TRANSAXLETroubleshooting (Basic Troubleshooting) (A540E and
A540H)AT±188

( ) 1: No fail±safe function X: Malfunctions
HINT: (A540H) When any one of the speed sensors (front or rear) or center differential control sole-
noid valves (No. 1 or No. 2) malfunction, the ECT ECU stops center differential control and main-
tains the center differential in a free condition.
Operating Mechanism for Each Gear (A540E A540H)
1. CLUTCH BRAKE AND ONE±WAY CLUTCH
A540E, A540H
Down±shift only ± no up±shift
2. SOLENOID SYSTEM
Possible gear positions in accordance with solenoid operating conditions.
A540E, A540H
NO. 2 SOLENOID
MALFUNCTIONING NO. I SOLENOID
MALFUNCTIONINGBOTH SOLENOIDS
MALFUNCTIONING Shift lever
positionGear position
NORMAL
D rangeParking
2 range
L rangeReverse
Neutral
Range
2nd3 rd
O/D
2nd1st
1st 1st2nd
3rd
± AUTOMATIC TRANSAXLETroubleshooting (Operating Mechanism for Each Gear
(A540E and A540H)AT±189

AT4B'
HINT: If codes 62, 63, 64, 73 or 74 appear, there is an electrical malfunction in the solenoid.
Causes due t mechanical failure, such as a stuck valve, will not appear.
If codes 44 and 61 appear, check the both (vehicle and rear wheel) speed sensors.
AT2020
HINT: If codes 62, 63 or 64 appear, there is an electrical malfunction in the solenoid. Causes due
to mechanical failure, such as a stuck valve, will not appear.
Severed No. 2 center differential control solenoid valve or short circuit
± severed wire harness or short circuit. Defective rear wheel speed sensor (in transfer left case) ±
severed wire harness or short circuit
Defective vehicle speed sensor (in differential carrier cover)
severed wire harness or short circuit
Severed No. 1 center differential control solenoid valve or short
circuit ± severed wire harness or short circuit. Defective No. 1 speed sensor (in combination meter) ±
severed wire harness or short circuit
DIAGNOSTIC CODES.
(A540E)
Severed lock±up solenoid or short circuit ±
severed wire harness or short circuit Severed lock±up solenoid or short circuit ±
severed wire harness or short circuitDefective No. 2 speed sensor (in ATM) ±
severed wire harness or short circuit
Severed No. t solenoid or short circuit ±
severed wire harness or short circuit
Severed No. 2 solenoid or short circuit ±
severed wire harness or short circuit Severed No. 1 solenoid or short circuit ±
severed wire harness or short circuit
Severed No. 2 solenoid or short circuit ±
severed wire harness or short circuitDiagnosis System
Diagnosis System Light Pattern
Light Pattern
(A540H)
Code No.
Code
No.
Normal Normal
± AUTOMATIC TRANSAXLETroubleshooting (Diagnosis System) (A540E and A540H)AT±192

6. Diagnostic code 73 (No. 1 center differential control solenoid valve circuitly)
Replace No. 1 and No. 2 center differ-
ential control solenoid valves.
HINT: No. 1 and No. 2 center differen-
tial control solenoid valves make a
set. Check resistance of No. 2 center differential con-
trol solenoid valve connector and body ground.
Resistance: 11 ± 15 Check resistance of No. 1 center differential control
solenoid valve connector and body ground.
Resistance: 11 ± 15 WReplace No. 1 and No. 2 center differ-
ential control solenoid valves.
HINT: No. 1 and No. 2 center differen-
tial control solenoid valves make a
set.
Check resistance of No. 2 center differential control
solenoid valve at ECT ECU connector.
(See page AT±219) Check resistance of No. 1 center differential control
solenoid valve at ECT ECU connector.
(See page AT±219)
7. Diagnostic code 74 (No. 2 center differential control solenoid valve circuitly)
Check wiring between No. 2 center differential con-
trol solenoid valve and ECT ECU. Check wiring between No. 1 center differential con-
trol solenoid valve and ECT ECU. Substitute another ECT ECU.
Substitute another ECT ECU.
± AUTOMATIC TRANSAXLETroubleshooting (Diagnosis System) (A540E and A540H)AT±198

MEASURE CENTER DIFFERENTIAL CONTROL PRESSURE (A540H Only)
(a) Warm up the transaxle fluid (122 ± 176°F or 50 ± 80°C)
(b) Measure the line pressure. (See page AT±224)
(e) Remove the transfer case test plug and mount the oil pressure gauge (SST).
SST 09992±00094
(d) Check the parking brake to see that it is fully applied chock the four wheels.
(e) Disconnect the connector from ECT ECU.
(f) Start the engine.
(g) Apply battery voltage to terminal SD1, or SD2 of the wire harness side connector and turn the No. .1
and No. 2 center differential control solenoid valves to either ON or OFF.
(h) Shift into the L range, step down strongly on the brake pedal with your left foot and while manipulating the
accelerator pedal with the right foot, measure the pressure at the engine speeds specified in the table.
kg/cm2 (psi, kPa)
HINT: After inspecting the center differential control pressure, erase the diagnosis codes (No. 73 and 74)
from the memory.
Condition of
Solenoid
ValvesNo. 1 Solenoid
Valve
No. 2 Solenoid
Valve
Engine
RPML range
Range
Idling
Stall
± AUTOMATIC TRANSAXLETroubleshooting (Mechanical System Tests) (A540E and
A540H)AT±226