Speedometer Vehicle Speed Sensor (VSS) -G22-, checking

If the speedometer is inoperative:

Check for speedometer vehicle speed sensor signal input to instrument cluster as follows:
Connect scan tool. Refer to VAG 1551/1552 Scan Tool (ST), VAS 5051 Vehicle Diagnostic Testing and Information System or VAS 5052 Vehicle Diagnostic and Service System, connecting and selecting functions .
Select "Read Measuring Value Block" function 08. Refer to Read Measuring Value Block (function 08) .
Select channel 001 and carry out road test.

WARNING:

When taking test readings while the vehicle is moving, VAG 1551/1552 or VAS 5052 must always be secured to the rear seat and operated from this position.
DO NOT USE VAS 5051 during a road test.

If the speed signal is indicated on the scan tool display, the instrument cluster is malfunctioning and must be replaced.

If the speed signal is not displayed on the scan tool display, the signal must be checked at the multi-pin terminal on the rear of the instrument cluster as follows:

Remove instrument cluster. Refer to Instrument cluster, removing and installing .
Connect test box VAG 1598 to blue 32-pin connector using adapter cable VAG 1598/25.
Perform an acoustic continuity test of wire and sensor using multimeter between socket 28 and socket 9 (load Ground)
Switch ignition off.

NOTE: For the Audi TT, the vehicle speed signal is generated by a hall effect sensor. Therefore, there must be battery voltage (about 12V) at the speedometer Vehicle Speed Sensor (VSS) -G22- during test.

Test:

Signal of continuity tester must switch off and on repeatedly while vehicle is rolled back and forth approximately 1 meter (1 yard).

If test is not OK:

Check wiring connection to speedometer vehicle speed sensor using applicable wiring diagram.

If test is OK:

Replace speedometer vehicle speed sensor.