4WD TOYOTA CAMRY V20 1986 Service Information

AT5032
(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 A241H automatic transaxle on the Corolla All-Trac/4WD Station Wagon. The fluid pressure
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
maintenance. Instructions concerning these handling methods are given on Camry Repair Manual
(Pub. No. RM199U) on page IN-8.
Hydraulic Multiplate ClutchTransfer Front DifferentialCenter
Differential 4-Speed Planetary Gear
Unit and Hydraulic
Control SystemNo. 1 and No. 2 Center Differential
Control Solenoid ValveCenter Differential ControlECT
ECU No. 1 and No. 2 Shift Control
Solenoid Valves and Lock-up
Control solenoid ValveEngine ECU
Throttle Position
Sensor
Stop Light Switch
Vehicle Speed
Sensors
Mode Select Switch
Neutral Start Switch
O/D Main Switch
Center Deff. Control
Switch Shift Control Sectional View
Sensors
- AUTOMATIC TRANSAXLEDescriptionAT-3

(Lever Type on 3S±FE Engine All±Trac/4WD Model)
± AIR CONDITIONING SYSTEMAir Conditioning System CircuitAC±6

(Push Type on 3S±FE Engine All±Trac/4WD Model)
± AIR CONDITIONING SYSTEMAir Conditioning System CircuitAC±7

WATER TEMPERATURE SWITCH
All±Trae/4WD Model
INSPECT SWITCH CONTINUITY
Inspect the switch continuity.
If detective, replace the water temperature
switch.If continuity is not as specified, replace the
relay. All±Trac/4WD Model
(A/C Cut Relay)
Apply battery voltage to
terminal 1 and 2Terminals
Condition
Constant
± AIR CONDITIONING SYSTEMRelaysAC±38

WATER TEMPERATURE SWITCH
All±Trae/4WD Model
INSPECT SWITCH CONTINUITY
Inspect the switch continuity.
If detective, replace the water temperature
switch.If continuity is not as specified, replace the
relay. All±Trac/4WD Model
(A/C Cut Relay)
Apply battery voltage to
terminal 1 and 2Terminals
Condition
Constant
± AIR CONDITIONING SYSTEMWater Temperature SwitchAC±38

1. REMOVEL LOWER AND UPPER UNIT CASES
(a) Discoonnect connectors
(b) Remove wire harness.
(c) Remove four clips.
(d) Remove five screws.
(e) Remove condenser fan control amplifier (2vZ±FE
E/G) or A/C cut amplifier (3S±FE E/G).
(f) Remove compressor control amplifier (2VZ±FE
E/G) or
A/C cut relay (All±Trac/4WD model).
(g) Remove upper unit case.
(h) Remove thermistor with thermistor holder.
(i) Remove lower unit case.
2. REMOVE EXPANSION VALVE
(a) Disconnect the liquid tube from the inlet fitting of the
expansion valve.
(b) Remove the packing and heat sensing tube from
suction tube of evaporator.
DISASSEMBLY OF COOLING UNIT
± AIR CONDITIONING SYSTEMCooling UnitAC±40

(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

UNDER BODY (All±Trac/4WD)
Nomenclature Nomenclature
Hole dia.
Hole dia.Symbol Symbol
± BODYBody DimensionsBO±78

Fuel Level Warning
INSPECTION OF LEVEL WARNING
1. INSPECT WARNING LIGHT OPERATION
(a) Disconnect the connector from the sender gauge.
(b) Connect terminals 1 and 2 on the wire harness side-
connector.
(e) Turn the ignition switch ON, check that the warning
light lights.
If the warning light does not light, test the bulb.
2. INSPECT WARNING SWITCH OPERATION
(a) Apply battery voltage to terminals 1 and 2 through a
3.4W test bulb, check that the bulb lights.
HINT: It will take a short time for the bulb to light.If resistance value is not as specified, replace the receiver
gauge.
3. INSPECT SENDER GAUGE OPERATION
(a) Connect a series of three 1.5V dry cell batterys.
(b) Connect the positive (+) lead from the dry cell batter-
ys to terminal 3 through a 3.4W test bulb and the neg-
ative (±) lead to terminal 4.
(c) Check that the voltage rises between terminals 3 and
4 as the float is moved from the top to bottom posi-
tion. 2. MEASURE RECEIVER GAUGE RESISTANCE
Measure the resistance between terminals.
(d) Measure the resistance between terminals 3 and 4
for each float position.
If operation is not as specified, replace the sender
gauge.
Between terminals
Resistance (W)
Resistance (W)
All±Trac/4WD Float position
mm (in.)
FWD
± BODY ELECTRICAL SYSTEMCombination MeterBE±37

Parking Brake
(For Rear Disc Brake)
COMPONENTS
2WD (w/o A.B.S.) and 4WD
2WD (w/ A.B.S.)
± BRAKE SYSTEMRear BrakeBR±42