U3846 Diagnostic Trouble Code

U3846 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 U3846 diagnostic trouble code may include:

Possible spark knock (detonation / pre-ignition)
Poor fuel economy
The engine oil will exhibit dilution from the ECUs attempts to increase engine temperature. Some vehicles advance the fuel injection timing slightly after top center to afterburn a small amount of fuel to increase exhaust temperatures. Some of this fuel enters the crankcase. When the ECU determines the necessity to regenerate the DPF, the service life of the oil be shortened significantly
Hesitation upon acceleration

Possible Causes :

A plugged converter will cause of host of driveability problems as well as set this code. A severely plugged converter will result in the inability to increase rpm when under load. Look for a code such as P0421 -- catalytic converter efficiency below threshold if the converter indicating a faulty converter.
Dirty air cleaner element Damaged DPF
Defective ECU strategies or components will prevent proper regeneration

Repair Processes :

You might continue by connecting the scanner to the vehicle diagnostic connector and retrieving all stored codes and freeze frame data. Look for damage to the tank indicating impact that may have damaged the fuel pump or sender.

Process Tips

Diagnostic trouble code U3846 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 U3846.

Fortunately, U3846 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

U3846 Trouble Code For Specific Cars

U3846 Riley 1.5-litre Hood Switch Circuit Failure
U3846 Bond Equipe Control Module Long Term Memory Performance/ Immobilizer Code Words Do Not Match
U3846 Diva 10f IAC Monitor Disabled by PSP Switch Failed On
U3846 Peugeot 204 ECU A/D Converter
U3846 Rover 200 Idle Switch (Electric Control Throttle) Circuit Malfunction
U3846 Daf 750 Gear select position Fault
U3846 Triumph Roadster PATS Transceiver Module Signal Is Not Received