Electronic control system [Toyota Camry Vista-V40]

Fuel injection system main relay

1. Remove the main fuel injection system relay.

2. Check the resistance of the relay winding.



a) Using an ohmmeter, check for conductivity between terminals "1" and "3" (resistance - 50-90 Ohm). Resistance between terminals "2" and "4" - 0 Ohm.

b) Then, using an ohmmeter, make sure there is no conductivity between terminals "4" and "5" (resistance is infinity).

3. Check the operation of the relay.

a) Apply voltage from the battery to terminals "1" and "3" of the relay connector.

b) Using an ohmmeter, check for conductivity between terminals "2" and "4".

b) Using an ohmmeter, check for conductivity between terminals "4" and "5".



If the conditions specified in points 1 and 2 are not met, replace the relay.

4. If necessary, the relay housing can be removed and, before throwing it away, try to eliminate the cause of the failure. To do this, clean all the contacts and check the resistance of the windings in both directions, since there may be diodes that shunt the windings. If the resistance of the windings in both directions is the same, there are no diodes, then the battery can be connected in any order. If not, then the battery should be connected observing the polarity.

5. Reinstall the relay.

Electric Fan Relay

1. Disconnect the negative terminal from the battery.

2. Remove the electric fan relay.

3. Check the electric fan relay.



Check for continuity between terminals "1" and "2" (50 - 8C Ohm) "3" and "4" (0 Ohm).

Fuel pump relay switch

Type 1

1. Remove the fuel pump switch relay.

2. Check the relay electrical circuit using an ohmmeter.

a) Check for conductivity between terminals: "STA" and "E1", "+B" and "FC".

b) Check for conductivity between terminals "+B" and "FP".



If the above conditions are not met, replace the relay.



3. Check the operation of the relay.

a) Apply voltage from the battery to the terminals "STA" and "E1" and use an ohmmeter to check for conductivity between the terminals "+B" and "FP".

b) Apply voltage from the battery to the "+B" and "FC" terminals and use an ohmmeter to check for conductivity between the "+B" and "FP" terminals.

If the relay operation is not as described, replace the relay.

4. Install the relay.

Type 2

1. Remove the fuel pump switch relay

2. Check the relay electrical circuit using an ohmmeter.

a) Check the resistance between terminals: "ST" and "E1", "IG" and "FC", "B" and "FC".

Resistance between terminals:

• "ST" and "E1" - 20-30 Ohm
• "IG" and "FC" — 110-170 Ohm
• "B" and "FC" - infinity

b) Apply battery voltage to terminals "ST" and "E1" and use an ohmmeter to check for conductivity between terminals "+B" and "FP".

If the relay operation is not as described, replace the relay.

Manifold Absolute Pressure Sensor

1. Check the supply voltage of the absolute pressure sensor in the intake manifold

a) Disconnect the absolute pressure sensor connector.

b) Turn on the ignition.

Using a voltmeter, measure the voltage between terminals "VC" and "E1" of the absolute pressure sensor connector.

• Nominal voltage - 4.5-5.5 V

2. Check the output signal of the absolute pressure sensor.

a) Turn on the ignition.

b) Disconnect the vacuum hose from the intake manifold.

c) Connect a voltmeter to the "PIM" and "E2" terminals of the electronic control unit connector and measure the output signal voltage at atmospheric pressure.

d) Stepwise apply a vacuum to the sensor within the range of 13.3 kPa (100 mmHg.) up to 66.7 kPa (500 mmHg.).

d) Measure the decrease in voltage for each vacuum value.

Coolant temperature sensor and intake air temperature sensor

Checking the coolant temperature sensor

1. To remove the coolant temperature sensor, drain the coolant.

2. Remove the sensor, disconnect the connector.

3. Using an ohmmeter, measure the resistance of the sensor.

4. Find the resistance value of the sensor from the graph (depending on the temperature) and compare with the measurement results.

If the resistance value is outside the tolerance shown in the graph, replace the sensor.



5. Reinstall the sensor.



6. Fill with coolant (If you removed the coolant temperature sensor).

Knock sensor

Checking the knock sensor

1. Disconnect the (-) cable from the negative battery terminal.

2. Remove the knock sensor, first disconnecting its connector.



3. Use an ohmmeter to check for conductivity between the sensor terminal and the housing. If not, replace the sensor.



4. Install the knock sensor back and connect its connector.

• Tightening torque - 44 Nm

5. Connect the (-) cable to the negative terminal of the battery.

Otherwise, replace the valve.

Idle Speed Increase Electro-Pneumatic Valve

Note: Valve configuration may differ from that shown.

1. Remove the valve.

2. Check the valve for an open circuit.

Using an ohmmeter, make sure that there is no break in the valve winding circuit by measuring its electrical resistance.

• Valve winding resistance value (in a cold state) is 4 Ohm

Otherwise, replace the valve.

3. Using an ohmmeter, one wire of which is alternately connected to the terminals of the valve connector, and the other to the valve body, make sure that there is no short circuit between the valve winding and the body ("ground").



If the ohmmeter registers any resistance other than infinity, replace the valve.

4. Check the valve operation:

a) Make sure that air does not pass from port "E" to port "F" through the valve.



b) Apply battery voltage to the valve connector terminals and make sure that air flows through post "E" to port "F". If not, replace the valve.





5. Install the valve back into place.

Checking the fuel vapor canister valve

1. Measure the resistance between the valve terminals.

• Resistance - 30-33 Ohm

2. Apply battery voltage and check the valve operation

Voltage:

• Served - air passes through
• Not supplied - air does not pass

Checking the check valve

1. Create a vacuum of 500 mmHg in the blue part of the valve and make sure that the vacuum is maintained.

2. Create a vacuum in the black side of the valve and make sure that air passes without resistance.

Oxygen sensor

Checking the oxygen sensor

1. Warm up the engine to normal operating temperature.

2. Measure the oxygen sensor feedback voltage.

Connect the positive lead of the voltmeter to the "VF1" terminal of the diagnostic connector and the negative lead to the "E1" terminal.



After this, perform the test (see below).

3. Check the resistance of the oxygen sensor heater.

Check the resistance between terminals "+B" and "HT".

• Resistance (at 20°C) - 11-16 Ohm

Checking the injection system elements

Table. Checking the injection system elements.

Oxygen Sensor Fault Finding Algorithm