With Manufacturer's Scan Tool

Oxygen Sensor (O2S) Aging (HO2S Before TWC), Checking

Special tools and equipment







- VAG1788/10 RPM adjuster







- VAS5051 with VAG5051/1

Test requirements:
- Coolant temperature at least 80 degree C.

Test sequence
- Connect vehicle diagnostic, testing and information system VAS 5051 and select vehicle system "01 -Engine electronics" in selection. Engine must be run at idle. Connecting VAS 5051/VAG 1551 Scan Tool (ST)

Display on VAS 5051:







- Under -1- select diagnostic function "04 - Basic setting".

Display on VAS 5051:







1 Enter display group, max entered value = 255
- Enter "034" for "display group number 034" in field -2- and confirm entry by pressing -Q- button.
- Set engine speed with V.A.G. 1788/10 RPM adjuster to 1800-2200/rpm.

Display on VAS 5051:







- Check specified value in display field -4-.

NOTE: This process can take several minutes.

Display Group 034:

Continued
If specified value in display field 3 and 4 is not obtained:
- Road test vehicle in order to free oxygen sensor of possible residue and repeat test.

If specified value in display field 3 and 4 is not obtained, even after road test:
- Replace Heated Oxygen Sensor (HO2S) -G39-.