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P1552

P1552

Function monitoring of control unit fault Group a - signal implausible

Diagnostic conditions
- Engine speed greater than 1120 rpm

Possible fault cause
- Fault "P0102" or "P0103" is set
- 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)]]
- DME control unit faulty

Affected terminals

-

Diagnosis/fault finding