1986 TOYOTA CAMRY V20 coolant

4. INSPECT WATER TEMPERATURE SWITCH
(a) Disconnect the switch connector.
(b) Using an ohmmeter, measure the resistance between
terminal 1 and body ground.
Coolant temperature:
Below 109
°F (43°C) 0

Above 131°F (55°C)
8

(c) Connect the switch connector.(e) Turn on the ignition switch and disconnect the water
temperature switch wire.
(f) Confirm that operation sounds of the solenoid can be
heard if the O/D main switch is repeatedly turn on
and off.
(g) Turn off the ignition switch and connect the water
temperature switch wire.
2. INSPECT O/D MAIN SWITCH
(a) Remove the console box.
(b) Using an ohmmeter, measure the resistance between
terminals 1 and 3.
wSwitch ON ± Resistance: 8


wSwitch OFF± Resistance: 0

3. INSPECT O/D OFF INDICATOR
(a) Turn on the ignition switch.
(b) Turn off the O/D main switch.
(c) Check that the O/D OFF indicator lights.
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140L)AT±37

Disconnect ECT ECU connector and road test.
Does the transaxle operate i n the respective gear
when in the following ranges while driving?
D range . . Overdrive
2 range . . 3 rd gear
L range . . . 1 st gear
TROUBLESHOOTING FLOW±CHART
Trouble No.1 No Shifting
Connect a voltmeter to the check connector termi-
nals Tt and E1.
Does ECT terminal voltage vary with changes in
throttle opening?
Is voltage between ECT ECU terminals
BK and GND as follows?
0V: Brake pedal released
10 ± 14 V: Brake pedal depressed Warm up engine
Coolant temp.: 17f6°F (80°C)
ATF temp.: 122 ± 176°F (50 ± 80°C)
wECU power source and ground faulty
wThrottle position signal faulty
wECT terminal wire open or short
Ye s
Continued on page AT±27Brake signal
faulty
Transaxle faulty Ye s
Ye s
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A±1 40E)AT±26

Connect a voltmeter to the check connector
terminals Tt and El.
Does ECT terminal voltage vary with changes in throttle
opening?
Check voltage between ECT ECU terminals
PWR and GND.
Power pattern: 10 ± 14V
Normal pattern: 1VIs voltage between ECT ECU terminals
BK and GND as follows?Tt
0V: Brake pedal released
10 ± 14V: Brake pedal depressed Warm up engine
Coolant temp.: 176°F (80°C)
ATF temp.: 122 ± 176°F (50 ± 80°C)
wECU power source and ground faulty
wThrottle position signal faulty
wECT terminal wire open or short
Faulty pattern select switch system
Shift point too high or too low
wFaulty ECT ECU
w|Faulty transaxle
Trouble No. 2
Brake sig-
nal faulty Ye s
Ye s
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140E)AT±28

Road test
Connect a voltmeter to the check connector
terminals Tt and El.
Is there 7, 5 or 3 V in the lock±up range while driving?
Is voltage between ECT ECU Terminals
BK and GND as follows?
Brake pedal depressed: 10 ± 14V
Brake pedal released: 0V Warm up engine ,
Coolant temp.: 176°F (80°C)
ATF temp.: 122 ± 176°F (50 ± 80°C)
wLock±up solenoid stuck
wFaulty transmission
wFaulty lock±up mechanism
wFaulty ECU power source and ground
w Faulty throttle position signal
No lock±up (After warm±up)
Faulty brake signal Trouble No. 4
Ye s
Ye s
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140E)AT±30

3. INSPECT EACH UP±SHIFT POSITION
(a) Warm up the engine.
Coolant temperature: 176
°F (80°C)
(b) Turn the O/D switch to ºONº.
(c) Place the pattern select switch in ºNormalº and the shift
lever into the D range.
(d) During a road test (above 10 km/h or 6 mph) check that
voltage at the ECT terminal is as indicated below for
each up±shift position.
If the voltage rises from 0V to 7V in the sequence
shown, the control system is okay.
The chart on the left shows the voltmeter reading and
corresponding gears. .
HINT: Determine the gear position by a light shock or
change in engine rpm when shifting. The lock±up clutch
will turn ON only infrequently during normal 2nd and 3rd
gear operation. To trigger this action, press the acceler-
ator pedal to 50% or more of its stroke. At less than
50%, the voltage may change in the sequence 2V ± 4V
± 6V ± 7V. 2. INSPECT BRAKE SIGNAL
(a) Depress the accelerator pedal until the ECT terminal
indicates 8V.
(b) Depress the brake pedal and check the voltage read-
ing from the ECT terminal.
(c) Brake pedal depressed . . . . . . . . . . 0V
Brake pedal released . . . . . . . . . . . . 8V
If not as indicated, there is a malfunction in either the
stop light switch or circuit.
INSPECTION OF Tt TERMINAL VOLTAGE
1. INSPECT THROTTLE POSITION SENSOR SIGNAL
(a) Turn the ignition switch to ON. Do not start the engine.
(b) Connect a voltmeter to terminals Tt and E1.
(c) While slowly depressing the accelerator pedal,
check that ECT terminal voltage rises in sequence.
if the voltage does not change in proportion to the
throttle opening angle, there is a malfunction in the
throttle position sensor or circuit.
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140E)AT±31

2. INSPECT SOLENOID
(a) Disconnect the connector from the ECT computer.
(b) Measure the resistance between S1, S2, SL and
ground.
Resistance: 11 ± 15


(c) Apply battery voltage to the solenoid. Check that an
operation noise can be heard from the solenoid.
HINT: If there is foreign matter in the solenoid valve,
there will be no fluid control even with solenoid opera-
tion.
3. CHECK SOLENOID SEALS
If there is foreign material in the solenoid valve, there
will be no fluid control even with solenoid operation.
(a) Check No. 1 and No. 2 solenoid valves.
wApplying 5 kg/cm2 (71 psi, 490 kPa) or compressed
air, check that the solenoid valves do not leak the air.
wWhen supply battery voltage to the solenoids,
check that the solenoid valves open.
(b) Check the lock±up solenoid valve.
wApplying 5 kglcm2 (71 psi, 490 kPa) of com-
pressed air, check that the solenoid valve
opens.
wWhen supply battery voltage to the solenoid,
check that the solenoid valve does not leak the
air.
Coolant temp. above 122°F (50°C) Coolant temp. below 122°F (50°C)
O/D main switch turned OFF O/D main switch turned ONMeasuring condition
Ignition switch ON
Vehicle movingStanding still
PWR pattern
NORM patternVoltage (V)
Terminal
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140E)AT±33

(e) Turn the O/D switch ON.
(d) Select the normal pattern.
(e) Drive .at around 50 km/h (31 mph) to where 7, 5 or 3
volts appears on the voltmeter (this is the lock±up
range) .
(f) Depress the accelerator pedal and read the tachometer.
If there is a big jump in engine rpm there is not lock±
up. 8. INSPECT PATTERN SELECTION SWITCH
Inspect that there is continuity between 5 and each ter-
minal. .
HINT: As there are diodes inside, be careful of the test-
er probe polarity.
10. INSPECT LOCK±UP MECHANISM
(a) Warm up the coolant and ATF.
(b) Connect a voltmeter to the check connector terminals
Tt and E1.
11. INSPECT BRAKE SIGNAL
Check that the brake light comes on when the brake
pedal is depressed. 9. INSPECT O/D SWITCH
Inspect that there is continuity between terminals 1 and 3.
S/W positionTerminal
Terminal Pattern
NORM
PWR
OFF
± AUTOMATIC TRANSAXLETroubleshooting (Electronic Control System) (A140E)AT±35

ROAD TEST (A140E)
NOTICE: Perform the test at normal operating fluid
temperature (122 ± 176°F or 50 ± 84°C). .
1. D RANGE TEST IN NORM AND PWR PATTERN
RANGES
Shift into the D range and hold the accelerator pedal
constant at the full throttle valve opening position.
Check the following:
(a) 1±2, 2±3 and 3±O/D up±shifts should take place, and
shift points should conform to those shown in the au-
tomatic shift schedule. (See page AT±49)
Conduct a test under both Normal and Power patterns.
HINT:
There is no O/D up±shift when coolant temperature is
below 122
°F (50°C).
There is no lock±up when the vehicle speed is 10 km/h (6
mph) less than the set cruise control speed.
EVALUATION
(1) If there is no 1 ± 2 up±shift:
wNo. 2 solenoid is stuck
w1±2 shift valve is stuck
(2) If there is no 2 ± 3 up±shift:
w No. 1 solenoid is stuck
w2±3 shift valve is stuck
(3) If there is no 3 ± O/D up±shift:
w3±O/D shift valve is stuck
(4) If the shift point is defective:
wThrottle valve, 1±2 shift valve, 2±3 .shift valve, 3±
wO/D shift valve etc., are defective
(5) If the lock±up is defective:
wLock±up solenoid is stuck
wLock±up relay valve is stuck
(b) In the same manner, check the shock and slip at the 1
±2, 2 ± 3 and 3 ± O/D up±shifts.
EVALUATION
If the shock is excessive:
wLine pressure is too high
wAccumulator is defective
wCheck ball is defective
(c) Run at the D range lock±up or O/D gear and check for
abnormal noise and vibration.
HINT: The check for the cause of abnormal noise and
vibration must be make with extreme care as it could
also be due to loss of balance in the drive shaft, tire,
torque converter, etc.
± AUTOMATIC TRANSAXLETroubleshooting (Mechanical System Tests) (A140L and
A140E)AT±43