U11C1 Diagnostic Trouble Code

U11C1 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 U11C1 diagnostic trouble code may include:

The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Faulty PCM
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Rich or lean exhaust

Possible Causes :

The Mass Airflow sensor will also cause this problem. Mass Airflow circuit malfunction.
Fuel with a large percentage of sulfur will clog the DPF quickly
An air leak forward of the DPF will change the sensor readings resulting in the code

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. Look at the plug wires to make sure they are not burnt or laying on the exhaust. Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications.

Process Tips

Diagnostic trouble code U11C1 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 U11C1.

Fortunately, U11C1 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U11C1 Trouble Code For Specific Cars

U11C1 Citroen C-zero Fuel Level Output Circuit Malfunction
U11C1 Franklin Airman Neutral Switch Circuit Malfunction
U11C1 Vauxhall Zafira A Pressure Transducer Redundant / Secondary Signal Faulted
U11C1 Austin 1300 Audio Single-Disc CD Player Internal Fault
U11C1 Volvo Xc70 I SCP (J1850) Invalid or Missing Data for Function Read Audible Warnings / Anti-Theft Module, Vehicle Immobilized
U11C1 Bugatti Type 73 Cylinder 2 Injector Circuit Low
U11C1 Opel Astra H DC-DC Converter Failure