Exhaust System: Testing and Inspection

Three Way Catalyst, checking





Special tools, workshop equipment, test and measuring appliances and aux. items required
^ VAG 1551 Scan Tool

Note:
VAG 1552 Scan Tool can be used instead of the VAG 1551; however, the VAG 1552 has no printer

^ VAG 1551/3 Adaptor cable
^ VAG 1788/10 RPM adjuster

Test sequence
- Connect VAG 1551/1552) Scan Tool
- Start engine and let idle
- Press 0 and 1 buttons to select Address Word 01: "engine electronics"





Display will appear as shown
- Press 0 and 4 buttons to select Function 04: "Basic setting"
- Press Q button to enter input





Display will appear as shown
- Press 0, 4 and 6 buttons to select "Display group 46
- Press 0 button to enter input





Display will appear as shown (1 to 4 = Display zones)
- Set engine speed with VAG 1788/10 speed adjuster between 2720 and 3320 rpm.
- Maintain engine speed between 2720 and 3320 rpm until value in display zone 4 jumps from "Test OFF" to "Test ON"!
- Continue maintaining engine speed between 2720 and 3320 rpm until specification "Cat. B1 OK" appears in display zone 4

Note:
Catalyst diagnostic lasts about 60 seconds.





If "Cat. 131 not OK" appears in display zone 4:
- Check Diagnostic Trouble Code memory:

If specification "Cat 131 OK" obtained:
- Remove VAG 1788/10 engine speed adjuster from throttle pedal.
- Press --> button.





Display will appear as shown
- Press 0 and 6 buttons to select Function 06: "End transfer"
- Press Q button to enter input