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P2193



P2193

Lambda Control Adaptation In Upper Load Range, Bank 2 (FRA02) - Above Limit Value

Diagnostic conditions - V8
- Battery voltage between 10 V and 16 V
- Lambda control active
- Engine temperature greater than 60 °C
- Mass air flow greater than 320 Kg/h
- Engine load for naturally aspirated engine greater than 26.3%
- Engine load for turbo engine greater than 82.5%

Diagnostic conditions - V6
- Battery voltage between 10 V and 16 V
- Lambda control active
- Engine temperature greater than 60 °C
- Mass air flow greater than 240 Kg/h
- Engine load greater than 24%

Possible fault cause
- Hot-film mass air flow sensor 1 and / or 2 faulty (setpoint voltage with stopped engine and ignition on = 0.9 to 1.1 V)=> see Actual values, Filter [ DME mass air flow ], [ Mass air flow 1 (sensor) ] + [ Mass air flow 2 (sensor) ]
- Fuel pressure too low
- Fuel pump delivery too low
- Mechanical fault in fuel injector (stuck)
- Incorrect main filling signal

Affected pins
DME control unit plug A, pin 29, and pin 5 of hot-film mass air flow sensor 1
Not V6 - DME control unit plug B, pin 109, and pin 5 of hot-film mass air flow sensor 2

Diagnosis/fault finding
- Diagnosis should indicate a positive deviation (enrichment) of more than 30% of the lambda control adaptation in the upper load range (FRAO greater than 1.3).
- V8 only - If this fault is set, both hot-film mass air flow sensors must always be tested because the main filling signal is calculated from both signals.