ABS/EDL and ABS/EDL/ASR ITT Mark 20 IE

The control module can transfer a number of measured values. These measured values supply information about the operating condition of the system or connected sensors. In many cases the transferred measured values are used to support troubleshooting and corrective actions. While these measured values can not be simultaneously evaluated, they are grouped in individual display group numbers which can be selected using the scan tool.

CAUTION: During troubleshooting ABS is inactive, This is not indicated by indicator light lighting up.

If a malfunction occurs in the system while "Check DTC memory" or "Read measuring value block" are being performed, it will be recognized by the control module and indicated by the ABS warning light - K47. This is an aid for tracing sporadic malfunctions.

- Connect VAG1551 and select address word 03 "Brake Electronics". Scan Tool VAG1551/1552 or VAS5051 Connecting/Selecting Function
- Check control module version and press --> button. Check Control Module Versions (Function 01)




Indicated on display
- Press buttons 0 and 8 for function "Read measuring value block."





Indicated on display
- Press Q button to confirm input.

Checking wheel speed sensor signal





Indicated on display
- Press buttons 0, 0 and 1.
- Press Q button to confirm input.





Indicated on display (vehicle at standstill)
The instantaneous wheel speeds are indicated. They serve to check the wheel speed sensor signal (wheel must be raised and turned by hand).





Display group 001

Notes:
^ By pressing buttons <-1 and 3 -> display group numbers can be selected continuously in sequence.
^ If you want to enter display group number manually then press C button.

Checking wheel speed sensor
The control module for ABS stores the first evaluated voltage signals from the wheel speed sensors when driving and shows them as true values in the measuring value block.





Indicated on display
- Press buttons 0, 0 and 2.
- Press Q button to confirm input.





Display group 002

Notes:
^ With vehicle at a stand still the value 2.55 km/h is indicated.
^ When driving measured values are shown as true values.

- Drive slowly until display of VAG1551 shows values.

Example





Indicated on display (when driving slowly)
The displayed values in display field 1 and 2 must not be greater than 6 km/h.
The displayed values in display field 3 and 4 must not be greater than 2 km/h. If values are greater than values listed, a malfunction related to wheel speed sensor installation may have occurred.
- Check installation of wheel speed sensor and impulse wheel for front axle.
- Check installation of wheel speed sensor and impulse wheel for rear axle.

Notes: By pressing buttons 1 and 3, display group numbers can be selected continuously in sequence.

- To enter display group number manually, press C button.

Testing function of brake light switch





Indicated on display
- Press buttons 0, 0 and 3.
- Press Q button to confirm input.





Display group 003

Notes:
^ By pressing buttons <-1 and 3-> display group numbers can be selected continuously in sequence.
^ If you want to enter display group number manually then press C button.

Checking communication status with Engine Control Module (ECM) and Transmission Control Module (TCM)





Indicated on display
- Press buttons 0, 0 and 4.
- Press Q button to confirm input.





Display group 004

Notes:
^ By pressing buttons <-1 and 3-> display group numbers can be selected continuously in sequence.
^ If you wart to enter display group number manually then press C button.

- Press --> button for On Board Diagnostic to return to "Select function" prompt.