TOYOTA CAMRY V20 1986 Service Information

3. INSPECT FUEL PRESSURE VSV
A. Inspect VSV for open circuit.
Using an ohmmeter, check that there is continuity between
terminals.
Resistance (Cold): 33 ± 39

If there is no continuity, replace the VSV.
INSPECTION OF FUEL PRESSURE
CONTROL SYSTEM.
1. INSPECT WATER TEMPERATURE SENSOR
(See page FI±49)
2. INSPECT INTAKE AIR TEMPERATURE SENSOR
(See page FI±37)
B. Inspect VSV for ground.
Using an ohmmeter, check that there is no continuity be-
tween each terminal and body.
If there is continuity, replace the VSV.
Fuel Pressure Control System
± EFI SYSTEMElectronic Control System (Fuel Pressure Control System)FI±127

(b) Apply battery voltage across the terminals
(c) Check that air flows from pipe E to filter.
If operation is not as specified, replace the VSV. C. Inspect VSV operation
(a) Check that air flow from pipes E to G.
± EFI SYSTEMElectronic Control System (Fuel Pressure Control System))FI±128

Main Oxygen Sensor
INSPECTION OF OXYGEN SENSOR
1. WARM UP ENGINE
Allow the engine to warm up to normal operating temperature.
2. INSPECT FEEDBACK VOLTAGE
Connect the positive (+) probe of a voltmeter to terminal VF1
of the check connector, and negative (±) probe to terminal
E1. Perform the test as follows:
Warm up the oxygen sensor with the engine at 2,500
rpm for approx. 90 seconds. And maintain engine at
2,500 rpm.
Normal code, code Nos. Malfunction code(s)
21, 25 and 26 (Ex. code Nos. 21, 25 and 26y Warm up the oxygen sensor with the engine at 2,500
rpm for approx. 90 seconds.
Disconnect terminals TE1 and E1 of the check connector.
And maintain engine speed at 2,500 rpm.Connect terminals TE1 and E1 of the check connector.
And maintain engine speed at 2,500 rpm.
Check the number of times the voltmeter needle
fluctuates in 10 seconds.Check the number of times the voltmeter needle fluctuates in 10 seconds.
Read and record diagnostic codes. (See page FI±25 or 27)Zero again After replacing
the oxygen sensor
Measure voltage between terminals VF 1 and E 1.
Repair the relevant diagnostic code.
CONTINUED ON PAGE FI±30Less than 8 times
Less than 8 timesReplace the ECU.
8 times of more
More than 0 V
8 times or
more
NormalZero
Zero
± EFI SYSTEMElectronic Control System (Main Oxygen Sensor)FI±129

Warm up the oxygen sensor with the engine at 2,500
rpm for approx. 90 seconds. And maintain engine speed at
2,500 rpm.Disconnect the water temp. sensor connector and connect
resistor with a resistance of 4 ± 8 k

or another coded
water temp. sensor.Disconnect terminals TE1 and E1 of the check connector.
And maintain engine at 2,500 rpm.
Measure voltage between terminals VF 1 and El.Rear record diagnostic codes. (See page FI±25 or 27) CONTINUED FROM PAGE FI±129
Malfunction code(s)
(Ex. code Nos. 21, 25 and 26)
Connect terminals TE1 and E1 of the check connector. Measure voltage between terminals VF 1 and E 1 .Measure voltage between terminals VF 1 and El.Normal code, code Nos.
21, 25 and 26 Repair the relevant diagnostic code.
Disconnect the PCV hose.
Replace the oxygen sensor.Repair (Over rich)
Repair (Over lean) More than 0 V
± EFI SYSTEMElectronic Control System (Main Oxygen SensorFI±130

Sub±Oxygen Sensor (CALIF. only)
INSPECTION OF SUB±OXYGEN
SENSOR
INSPECT SUB±OXYGEN SENSOR
HINT: Inspect only when code No.27 is displayed.
(a) Diagnostic code cancellation.
(See page FI±24)
(b) Warm up the engine until it reaches normal operating
temperature.
(a) (M/T)
Drive for 5 minutes or more between 80 km/h (50
mph) and 100 km/h in 4th or 5th gear.
(A/T)
Drive for 5 minutes or more between 80 km/h (50
mph) and 100 km/h (62 mph) in ºDº range.
(d) Following the conditions in step (e), press fully on the
accelerator pedal for 2 seconds or more.
HINT: Do not exceed 100 km/h (62 mph), or diagnostic code
will be cancelled.
(e) Stop the vehicle and turn the ignition switch to OFF.
(f) Carry out steps (b), (c) and (d) again to test acceleration.
If code No. 27 reappears again, check the sub±oxygen sensor
circuit. If the circuit is normal, replace the suboxygen sen-
sor. 3. (2VZ±FE)
INSPECT HEATER RESISTANCE OF OXYGEN
SENSOR
Using an ohmmeter, measure the resistance between the
terminal +B and HT.
Resistance (Cold): 5.1 6.3
at 20°C (68°F)
If the resistance is not as specified, replace the sensor.
± EFI SYSTEMElectronic Control System (Main Oxygen SensorFI±131

Sub±Oxygen Sensor (CALIF. only)
INSPECTION OF SUB±OXYGEN
SENSOR
INSPECT SUB±OXYGEN SENSOR
HINT: Inspect only when code No.27 is displayed.
(a) Diagnostic code cancellation.
(See page FI±24)
(b) Warm up the engine until it reaches normal operating
temperature.
(a) (M/T)
Drive for 5 minutes or more between 80 km/h (50
mph) and 100 km/h in 4th or 5th gear.
(A/T)
Drive for 5 minutes or more between 80 km/h (50
mph) and 100 km/h (62 mph) in ºDº range.
(d) Following the conditions in step (e), press fully on the
accelerator pedal for 2 seconds or more.
HINT: Do not exceed 100 km/h (62 mph), or diagnostic code
will be cancelled.
(e) Stop the vehicle and turn the ignition switch to OFF.
(f) Carry out steps (b), (c) and (d) again to test acceleration.
If code No. 27 reappears again, check the sub±oxygen sensor
circuit. If the circuit is normal, replace the suboxygen sen-
sor. 3. (2VZ±FE)
INSPECT HEATER RESISTANCE OF OXYGEN
SENSOR
Using an ohmmeter, measure the resistance between the
terminal +B and HT.
Resistance (Cold): 5.1 6.3
at 20°C (68°F)
If the resistance is not as specified, replace the sensor.
± EFI SYSTEM
Sub±Oxygen Sensor (CALIF. only)FI±131

2. INSPECT VOLTAGE OF ECU
Check the voltage between each terminal of the wiring con-
nectors.
wTurn the ignition switch ON.
wMeasure the voltage at each terminal.
HINT:
wPerform all voltage measurements with the connectors
connected.
wVerify that the battery voltage is 11 V or more when the
ignition switch is ON.
Electronic Controlled Unit (ECU)
INSPECTION OF ECU
HINT: The EFI circuit can be checked by measuring the
resistance and voltage at the wiring connectors of the ECU.
1. (2VZ±FE)
PREPARATION (See page FI±50)
± EFI SYSTEMElectronic Control System (Electronic Controlled Unit
(ECU))FI±132

Voltage at ECU Wiring Connectors (3S±FE)
No trouble (ºCHECKº engine warning light off) and engine running
Stop light SW 4N (Brake pedal depressed) or defogger SW ONCheck connector TE1 ± E1 not connected
Check connector TE 1 ± E 1 connectedMeasuring plate fully closed
Ex. shift position P or N rangeIntake air temp. 20°C (68°F)
Coolant temp. 80°C (1 760F) Measuring plate fully open
Shift position P or N rangeThrottle valve fully closedThrottle valve fully closed
Heater blower SW ON Air conditioning ONThrottle valve open
Throttle valve open
Throttle valve open
Cranking or idlingIG SW ONSTD voltage (V) Condition
3,000 rpm
IG SW ONIG SW ON1G SW ON
IG SW ON Terminals
IG SW ON
CrankingIdling
± EFI SYSTEMElectronic Control System (Electronic Controlled Unit(ECU))
FI±133

Voltage at ECU Wiring Connectors (2VZ±FE)
No trouble (ºCHECKº engine warning light off) and engine running
Stop light SW ON (Brake pedal depressed)Check connector TE1 ± E1 not connected
Check connector TE1 ± E1 connected
Ex. shift position P or N range Measuring plate fully closed
Intake air temp. 20°C (68°F)
Coolant temp. 80°C (176°F) Measuring plate fully open
Shift position P or N range Throttle valve fully closed
Heater blower SW ON Air conditioning ON Throttle valve open Throttle valve open
Cranking or idlingSm voltage (V)
3,000 rpm IG SW ON
IG SW ON
IG SW ON
IG SW ON
IG SW ON 1G SW ON Terminals
Cranking Idling
± EFI SYSTEMElectronic Control System (Electronic Controlled Unit(ECU))
FI±134

2. INSPECT RESISTANCE OF ECU
NOTICE:
wDo not touch the ECU terminals.
wThe tester probe should be inserted into the wiring
connector from the wiring side.
Check the resistance between each terminal of the wiring
connectors.
wDisconnect the connectors from the ECU.
wMeasure the resistance at each terminal.
Resistance of ECU Wiring Connectors (3S±FE)
Measuring plate fully closed
Intake air temp. 20
°C (68°F)
Coolant temp. 80°C (176°F)
Measuring plate fully openThrottle valve fully closed
Throttle valve fully closedThrottle valve fully closed
Throttle valve fully closedThrottle valve fully open
Throttle valve fully openThrottle valve open
STD resistance ()
Throttle valve open
Condition Terminals
± EFI SYSTEMElectronic Control System (Electronic Controlled Unit
(ECU))FI±135