Fuel and Air Ratios, Control Module

WARNING: This page is about a different car, the 2009 Audi A4, 2008 Audi A4, 2007 Audi A4, 2006 Audi A4, and 2005 Audi A4. However, it is still accessible from the selected car via links, so may be relevant.

DTC	Error Message	Diagnostic Procedure	Malfunction Criteria and Threshold Value	Secondary Parameters with Enable Conditions	Monitoring Time Length	Frequency of checks, MIL Illum
P12A1	Fuel Rail Pressure Sensor Inappropriately High	Check the Fuel Pressure Sensor G247. Refer to → Fuel Pressure Sensor G247 , Checking .	Deviation fuel rail pressure control -0.015 g And Deviation lambda control -25%	Fuel cut off, Not active Engine speed, 640-3480 rpm Time after engine start, >250 sec. High pressure pump set point, 0.005-0.05 g Lambda control, Closed loop EVAP canister load, 25%	5 Seconds	Continuous 2 DCY
P12A2	Fuel Rail Pressure Sensor Inappropriately High	Check the Fuel Pressure Sensor G247. Refer to → Fuel Pressure Sensor G247 , Checking .	Deviation fuel rail pressure control -0.01 g And Deviation lambda control >30%	Fuel cut off, Not active Engine speed, 640-3480 rpm Time after engine start, >250 sec. High pressure pump set point, 0.005-0.05 g Lambda control, Closed loop EVAP canister load, 25%	5 Seconds	Continuous 2 DCY
P12A4	Fuel Rail Pump Control Valve Stuck Closed	Check the Low Fuel Pressure Sensor G410. Refer to → Low Fuel Pressure Sensor G410 , Checking .	Deviation fuel rail pressure control -0.025 g And Deviation lambda control -1010%	Fuel cut off, Not active Engine speed, 640-3480 rpm Time after engine start, >250 sec. High pressure pump set point, 0.005-0.05 g Lambda control, Closed loop EVAP canister load, 25%	5 Seconds	Continuous 2 DCY

DTC

Error Message

Diagnostic Procedure

Malfunction Criteria and Threshold Value

Secondary Parameters with Enable Conditions

Monitoring Time Length

Frequency of checks, MIL Illum

P12A1

Fuel Rail Pressure Sensor Inappropriately High

Check the Fuel Pressure Sensor G247. Refer to → Fuel Pressure Sensor G247 , Checking .

Deviation fuel rail pressure control -0.015 g
And Deviation lambda control -25%

Fuel cut off, Not active
Engine speed, 640-3480 rpm

Time after engine start, >250 sec.
High pressure pump set point, 0.005-0.05 g

Lambda control, Closed loop
EVAP canister load, 25%

5 Seconds

Continuous
2 DCY

P12A2

Fuel Rail Pressure Sensor Inappropriately High

Check the Fuel Pressure Sensor G247. Refer to → Fuel Pressure Sensor G247 , Checking .

Deviation fuel rail pressure control -0.01 g
And Deviation lambda control >30%

Fuel cut off, Not active
Engine speed, 640-3480 rpm

Time after engine start, >250 sec.
High pressure pump set point, 0.005-0.05 g

Lambda control, Closed loop
EVAP canister load, 25%

5 Seconds

Continuous
2 DCY

P12A4

Fuel Rail Pump Control Valve Stuck Closed

Check the Low Fuel Pressure Sensor G410. Refer to → Low Fuel Pressure Sensor G410 , Checking .

Deviation fuel rail pressure control -0.025 g
And Deviation lambda control -1010%

Fuel cut off, Not active
Engine speed, 640-3480 rpm

Time after engine start, >250 sec.
High pressure pump set point, 0.005-0.05 g

Lambda control, Closed loop
EVAP canister load, 25%

5 Seconds

Continuous
2 DCY