Vehicle Speed Sensor: Testing and Inspection

VEHICLE SPEED SIGNAL, CHECKING

Special tools, testers and auxiliary items
- VAG 1551/1552 scan tool with VAG 1551/3 adapter cable
- Multimeter (Fluke 83 or equivalent)
- Connector test kit VW 1594
- Wiring diagram

Test conditions
- Speedometer OK, checking:

NOTE: To check the speed sensor signal the vehicle must be test driven. To do this a second person is necessary.

Test sequence
- Engine running at idle
- Connect VAG 1551/1552 scan tool and select "Engine Electronics" address word 01. Refer to "On-Board Diagnostics II With VAG 1551". Testing and Inspection

Indicated on display

Rapid data transfer HELP
Select function XX

- Press buttons -0- and -8- to select "Read Measuring Value Block" function 08 and press -Q- button to confirm input.

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press buttons -0-, -0- and -5- for display group 005 and press -Q- button to confirm input.

Indicated on display (1-4 = Display fields)

Read Measuring Value Block 5 ->
1 2 3 4

- Carry out test drive and observe display in display field 3 (second technician necessary).





- Press -> button.
- Press buttons -0- and -6- to select "End Output" function 06 and press -Q- button to confirm input.
- Switch ignition off.

Continuation

If no speed is indicated:





- Disconnect 3-pin connector from vehicle speed sensor -1-.
- Switch ignition on.





- Connect multimeter using test leads from VW 1594 to measure voltage at terminals 1 and 3 of connector. Specification: 9-14.5 volts
- Switch ignition off.
- Reconnect connector

If no voltage was present:
- Check wiring according to wiring diagram.

If voltage was 9-14.5 volts:





- Connect VAG 1598/18 test box to ECM wiring harness.
- Check wiring between central electrical panel and test box socket 65 for open circuit according to wiring diagram.

Resistance: maximum 1.5 Ohms

- Connect multimeter using test leads from VW 1594 to measure voltage at sockets 56 and 65.
- Switch ignition on.
- Lift left front wheel and rotate by hand or push vehicle.

- The voltage value must fluctuate between 0 and at least 4 volts.

If no wiring malfunction is detected and voltage was present between terminals 1 and 3:
- Replace Speedometer Vehicle Speed Sensor (VSS) -G22-.
- Read the readiness code. If DTC memory has been erased, repair must be verified via appropriate display group See Readiness code, creating. Refer to "On-Board Diagnostics II With VAG 1551". Testing and Inspection