Checking the inlet air temperature sensor (on AEY, ANV, AKW engines) (VW Polo 3)

Connect the VAG 1551 tester and dial "01" to select the "Address word" function of the engine control unit. The engine should be idling. The display should show the following information:

2. Press "08" to select the "Read measured value block" function and confirm by pressing the "Q" key. The following information should appear on the display.

3. Press "007" to select the "Display Group 7" function and press "Q". The display should show the following information:

4. If there is no actual display in field 3 or the temperature displayed is 18.9°C or 136.8°C, check the temperature sensor and wires.

6. Click "→".

7. Press "06" to select the "Complete Output" function and confirm by pressing the "Q" button.

8. Turn off the ignition.

9. Disconnect the wiring connector 1 from the sensor 2 (Fig. 6.84). Measure the resistance between the sensor contacts. The specified value is shown in Fig. 6.85. Area A shows the resistance in the temperature range of 0-50°C, area B - the resistance in the temperature range of 50-100°C. For example, a temperature of 30°C corresponds to a resistance of 1500-2000 Ohm; temperature 80°C corresponds to resistance 275-375 Ohm.

9. Disconnect the wiring connector 1 from the sensor 2 (Fig. 6.84). Measure the resistance between…

10. If the specified value is not achieved, replace the sensor.

11. If the specified value is reached:

On vehicles with a 68-pin control unit wiring connector

Connect the VAG 1598/18 tester to the engine control unit wiring harness (fig. 6.54);
Check the wire between the tester and the connector for open circuit; contact 1 + socket 64, contact 2 + socket 33 (Fig. 6.86). Set value: 1.5 Ohm;
Additionally, check the wires for short circuits to each other, to the vehicle ground, and to the positive battery terminal. Specification resistance: ∞ Ohm;

On vehicles with 80-pin control unit wiring connector

Connect the VAG 1598/22 tester to the engine control unit wiring harness (fig. 6.56);
Check the wire between the tester and the connector for open circuit: contact 1 and socket 13, contact 2 and socket 25 (Fig. 6.86). Specified value: 1.5 Ohm;
Additionally, check the wires for short circuits to each other, to the vehicle ground, and to the positive battery terminal. Specification resistance: ∞ Ohms.

The original article is available on the website: VWmanual.ru