C0446 Diagnostic Trouble Code

C0446 is a kind of OBD-II Diagnostic C-Chassis 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 C0446 diagnostic trouble code may include:

Faulty O2 Sensor
Lack of power
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Diminished fuel efficiency

Possible Causes :

The Mass Airflow sensor is a hot wire that senses the volume of air entering the intake manifold. The computer uses this information to control fuel mixture.
Defective ECU strategies or components will prevent proper regeneration
Fuel with a large percentage of sulfur will clog the DPF quickly

Repair Processes :

Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector. 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 C0446 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 C0446.

Fortunately, C0446 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C0446 Trouble Code For Specific Cars

C0446 Innocenti 950 SCP (J1850) Invalid or Missing Data for Function Read Fuel System
C0446 Franklin 11 Needle Lift Sensor Malfunction
C0446 Suzuki Grand Vitara
C0446 Porsche 904 Front Wiper Motor Relay Circuit Short to Vbatt
C0446 Tata Nano Mirror Passenger Vertical Feedback Potentiometer Circuit Short to Ground
C0446 Maserati 4 Transmission Control System MIL Request Circuit High
C0446 Seat 133 Injector Circuit Malfunction - Cylinder 2