Audi fuel pump diagnosis
This TSB applies to 2011-2012 Audi A4/A5/Q5 vehicles. Due to a stored DTC in Engine Electronics related to the in-tank fuel pump, the in-tank fuel pump and its circuits require diagnosis.
Portions of the fuel pump circuitry which are monitored by the on-board diagnostics are inside the control unit for fuel pump electronics. Any diagnosis of the in-tank fuel pump should include diagnosis and evaluation of the control unit for fuel pump electronics.
Complete all GFF test plans related to the customer concern and repair as necessary.
Perform the fuel pump diagnostics published in ELSA under Engine >>> Fuel Supply >>> Diagnosis and Testing for Fuel Pump Electrical Checking and Fuel Pump Delivery Rate Checking. Repair as necessary.
If the source of the concern is not clearly isolated using GFF test plans and ELSA diagnostics, inspect both the internal and external electrical connections of the fuel supply unit, including the fuel pump. Ensure all pins are in good condition and connections are secure, including the electrical connectors at the control unit for fuel pump electronics.
If a clear cause of the customer concern is not identified during the preceding diagnosis, replace the control unit for fuel pump electronics.