2010 Mercedes Benz C 300 (204.054) V6-3.0L (272.947) Page 801

Test 2.1.6.3: Check reference signal of component B2/5 (Hot film mass air flow sensor).

2.1.6.1. Check signal of component B2/5 (Hot film mass air flow sensor) via actual value with engine OFF.

Warning!Communication with ECU required.

2.1.6.2. Check signal of component B2/5 (Hot film mass air flow sensor) via actual value with engine speed greater than 3500 rpm.

Warning!Communication with ECU required.

2.1.6.3. Check reference signal of component B2/5 (Hot film mass air flow sensor).

Test sequence

- Switch on ignition.

Status of relevant actual value:

- HFM-SFI ( Reference signal ):Warning! Communication with ECU required.

Specified value

- Reference signal[46...59] ms

Question

- Is the measurement value OK?

YES

The actual value is okay.End of test

NO

The actual value is not o.k.Possible cause and remedy

- Check lines from component N3/10 (ME-SFI [ME] control unit) to component B2/5 (Hot film mass air flow sensor).

- B2/5 (Hot film mass air flow sensor)

2.1.7. Check seal of component B2/5 (Hot film mass air flow sensor) with air filter for cracks.

Possible cause and remedy

- Check seal of component B2/5 (Hot film mass air flow sensor) with air filter for cracks.

Note

- Proper sealing between the air cleaner housing and the housing of the HFM mass air flow sensor must be assured.