FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Manufacturer's Scan Tool



Oxygen Sensor Aging, Oxygen Sensor Before Three Way Catalytic Converter (TWC), Checking

Special tools, test equipment and auxiliary items






- VAG 1551 scan tool or VAG 1552 mobile scan tool with VAG 1551/3B cable
- VAG 1788/10 RPM adjuster

Test conditions
- Engine Coolant Temperature (ECT) must be at least 80 °C, see display group 04, display zone 3

Functional check
- Connect VAG 1551 scan tool (or VAG 1552). Start engine and select "Address word" 01 of Motronic Engine Control Module (ECM) -J220-. Engine must be running at idle speed. Connecting scan tool and selecting Motronic Engine Control Module (ECM) -J220-. [1][2][3]Connecting VAG 1551 Scan Tool

Indicated on display


Rapid data transfer HELP
Select function XX



- Press buttons -0- and -4- for function "Basic Setting" and confirm entry with -Q- button.

Indicated on display


Basic setting
Input display group number XXX



- Press buttons -0-, -3- and -4- for "Display group number 34" and confirm entry with -Q- button.

Indicated on display (1 to 4 = Display zones)


System in basic setting 34 ->
1 2 3 4



- Adjust RPMs with VAG1788/10 RPM adjuster to 1800 to 2200 RPM.
- Check specifications in display zones 1 to 4.
- Maintain engine speed at 1800...2200 rpm until display in display zone 4 jumps from "Test OFF" to "Test ON". Three Way Catalytic Converter (TWC) temperature in display zone 2 must be 350 to 500 °C
- Continue to maintain speed at 1800...2200 rpm until specification "B1-S1 OK" appears in display zone 4.







If the specifications are obtained:
- Press -> button.
- Remove engine speed adjuster VAG 1788/10 from accelerator pedal.
- Press buttons -0- and -6- for function "End output" and confirm entry with -Q- button.
- Switch off ignition.

Continuation

If the specifications are not obtained:
- Remove engine speed adjuster VAG 1788/10 from accelerator pedal.
- Road test vehicle to free oxygen sensor of possible contaminates and repeat test.
Observe the valid safety precautions when carrying out a road test.

If the specifications are again not obtained:
- Replace oxygen sensor before Three Way Catalytic Converter (TWC) -G39-, item 10.
- Check DTC Memory, if necessary, repair any malfunctions and then Erase DTC Memory, Checking and Erasing DTC Memory. Reading Diagnostic Trouble Codes
- Read readiness code. If DTC memory has been erased or Motronic Engine Control Module (ECM) -J220- was disconnected from battery positive, readiness code must be generated again.
Monitors, Trips, Drive Cycles and Readiness Codes
Monitors, Trips, Drive Cycles and Readiness Codes