U0306 Diagnostic Trouble Code

U0306 is a kind of OBD-II Diagnostic U-Network Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a U0306 diagnostic trouble code may include:

Corroded or damaged connector
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Lack of power
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.

Possible Causes :

Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
Rough running engine due to misfiring plugs. Many engines have misfire codes to indicate the cylinder effected, such as P0307 for number 7.

Repair Processes :

Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness. It should be pretty close to battery voltage (12 volts). If not, then this is the circuit that has the problem.

Process Tips

Diagnostic trouble code U0306 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before U0306.

Fortunately, U0306 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P1205 Trouble Code For Specific Cars

U0306 Saturn Sl Incorrect Module Design Level
U0306 Daihatsu Sirion Glow Plug Circuit Low Input (Bank #1)
U0306 Suzuki C2 Memory 2 Switch Circuit Short To Battery
U0306 Marmon V16 Transmission 4-Wheel Drive Mode Select Circuit Failure
U0306 Mg Mgb Air Suspension Vent Solenoid Output Circuit Open
U0306 Facel Vega Excellence Injection Timing Control Circuit Malfunction
U0306 Porsche 901 Front Wiper Motor Relay Circuit Open (changed from Failure 2/6/97)