Checking the supply voltage for the engine control unit (VW Lt 2d)

1. Connect the VAG 1551 tester and, by entering "01" "Engine electronics", select the engine control unit. The engine should be idling. The display should show the following information:

• Fast data exchange HELP
• Dial function XX

2. Press "08" to select the "Read Block of Measured Values" function and confirm with the "Q" button. The display should show the following information:

• Reading the measured value block HELP
• Enter group number XXX

3. Press "005" to select the "Display Group 005" function and press "Q". The display should show the following information:

Reading block of measured values 2 → 1 2 3 4

4. Read the voltage value in field 3 of the display. The specified value is 11.0 V.

5. Click "→".

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

7. Turn off the ignition.

8. If the specified value is not reached, connect the VAG 1598/26 tester.

Checking the voltage at terminal 30

9 Measure the voltage between sockets 1 (red) and 10 (red) of the tester using a multimeter and an additional VAG 1594 lead. Specified value: 11.0 V

10. If the specified value is not achieved, check the connection of the wires to the central electrical system using the wiring diagram.

Checking the voltage at terminal 15

11. Connect the multimeter between sockets 1 (red) and 1 (red) of the tester with an additional VAG 1594 wire.

12. Turn on the ignition. Set value: 11.0 V.

13. If the specified value is not achieved, check the connection of the wires to the central electrical system using the wiring diagram.



The original text can be found on the portal: VWManual.ru

14. Disconnect the VAG 1598/26 tester.