Vehicle Speed Sensor: Testing and Inspection

Vehicle Speed Signal, Checking

Special tools and equipment
- VAG 1551 Scan Tool or VAG 1552 with cable VAG 1551/3
- Test box VAG 1598/22
- Hand multimeter VAG 1526 or multimeter VAG 1715 Adapter set VAG 1594
- Wiring diagram

Check conditions
- The battery voltage must be at least 11.5 V.
- Speedometer must be OK, checking speedometer:

Test sequence

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

WARNING: Secure scan tool to rear seat and operate from this position.

- Connect VAG 1551 Scan Tool ((VAG 1552). Start engine and select "Address word" 01 of engine control module. When doing this engine must be running at idle speed. (Connecting scan tool and selecting engine control module [1][2][3]Connecting VAG Scan Tool 1551/1552).

Indicated on display

Rapid data transfer HELP
Select function XX

- Press keys 0 and 8 for function "Read Measuring Value Block" and confirm entry with Q key.

Indicated on display

Read Measuring Value Block HELP
Input display group number XXX

- Press keys 0, 0 and 5 for "Display group number 5" and confirm entry with Q key.

Indicated on display: (1 to 4 = Display zones)

Read Measuring Value Block 5 ->
1 2 3 4

- Test drive vehicle with a 2nd person to observe display.
- Observe figure displayed in display zone 3:
Specification: approx. driven speed
- Press -> key.
- Press keys 0 and 6 for "End Output" function and confirm input with Q key.
- Switch ignition off.

If no speed is displayed:







- Connect test box VAG 1598/22 to control module wiring harness.
- Connect multimeter to measure voltage between test box sockets 2+20.
- Switch ignition on.
- Lift vehicle at front left.
- Rotate front wheel and observe voltage display.
Specification: between 0 and at least 4 Volt fluctuating

If the display does not fluctuate:
- Check wiring to speedometer/speedometer sensor.