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Oxygen Sensors Before Catalytic Converter, Checking Aging



Oxygen Sensors Before Catalytic Converter, Checking Aging

Special tools and equipment







- VAS5051 with VAS5051/1

Test requirements:
- Engine coolant temperature at least 80 degrees C, display group 004, display zone 3.

Test sequence
- Connect testing and information system VAS5051 and select vehicle system "01 - Engine electronics" in selection. Engine must be running at idling speed.







Display on VAS5051:
- Under -1- select diagnostic function "04 - Basic setting".







Display on VAS5051:
1. Enter display group
- Select function "197" in button field -2- for "display group number 197" and press -Q- button to confirm input.







Display on VAS5051:
- Activate basic setting by pressing -A- button.
- Press accelerator and brake pedal simultaneously, engine speed increases to approx. 2200 rpm.

Test conditions:
- Accelerator and brake pedal pressed simultaneously, engine runs at approx. 2200 rpm.

- Check specifications in display zones -3- and -4-.







Note on display zones 1 and 3:
The dynamics factor is the characteristic for the aging of the oxygen sensor. The lower the dynamics factor the more advanced is the aging of the oxygen sensor.
- Press square button.
(cont.)

If specification in display zone 3 or 4 is not obtained:
- Perform test drive to free oxygen sensors from any possible residues and repeat test.

If specified value in display zone 3 or 4 is not obtained, after a test drive has been performed:
- Replace relevant oxygen sensor before catalytic converter.