With Manufacturer's Scan Tool

Vehicle Speed Sensor (VSS) Signal, Checking

Special tools and equipment







- VAG1526A
- VAG1527B
- VAG1594A
- VAG1598/31
- VAS5051 with VAG5051/1

NOTE:
- The vehicle speed signal is generated by the Speedometer Vehicle Speed Sensor (VSS) -G22- (at transmission) and processed in the instrument cluster.
- The processed signal enters at terminal 54 of the ECM and is used for idle stabilization and tip-in shock reduction during shifting.

Test requirement:
- Function and display of speedometer OK. Troubleshooting:

Test sequence

WARNING: To reduce the danger of accident during road tests, always observe safety precautions. Technician Safety Information

- Connect VAS5051 scan tool and select control module for engine electronics using "address word" 01. Engine must run at idle for this. Connecting VAS 5051/VAG 1551 Scan Tool (ST)

Display on VAS 5051:







- Select from the display -1- the diagnostic function "08 - Read Measuring Value Block".

Display on VAS 5051:







1 - Enter display group, max. entered value = 255
- Enter "005" for "display group number 005" in field -2- and confirm entry by pressing -Q- button.

Display on VAS 5051







- Determining via road test whether vehicle speed is displayed in display field 3.
- If vehicle speed is not displayed, lift vehicle -if possible using a vehicle lift- until front left wheel is free.
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM. Electrical Testing Using VAG1598/31 Test Box
- Connect VAG1527B voltage tester to sockets 3 (B+) and 54 (VSS) of VAG1598/31 test box.
- Switch ignition on and turn front left wheel by hand.
- LED must blink (very brief blink signal).

If LED does not blink:
- Check the following wire connection for open circuit and short circuit to Ground (GND) and B+:

Test box V.A.G 1598/31 Instrument cluster:
Socket Terminal
54

- Repair open circuit or short circuit if necessary.