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U0123 Engine Trouble Code

Meaning of U0123 engine trouble code is a kind of network trouble code and when your car's 'U0123 Check Engine' light comes on, it's usually accompanied by a sinking feeling in the pit of your stomach. The light could mean a costly problem, like a bad catalytic converter, or it could be something minor, like a loose gas cap. But in many cases, it means at minimum that you'll be visiting the car dealer to locate the malfunction and get the light turned off.

U0123 Fault Symptoms :

Check engine light comes on
Engine stalling or misfiring
Engine performance issues
Car not starting

If one of these reasons for U0123 code is occuring now you should check U0123 repair processes.
Now don't ask yourself; What should you do with U0123 code ?
The solution is here :

U0123 Possible Solution:

Disconnected, dirty or fouled spark plugs are common causes for engines that won't start. Spark plugs typically need to be replaced every season or 25 hours of use. You should also check that the spark plug gap is set properly. If your spark plugs look good, problems with your ignition system can also preventing a spark. These can range from a faulty spark plug lead, shorted kill switch or flywheel key damage.

U0123 Code Meaning :

U	0	1	2	3
OBD-II Diagnostic Network (U) Trouble Code For Engine	Intake Valve Control Solenoid Circuit Low	Fuel Rail/System Pressure - Too High	Turbocharger Boost Sensor A Circuit Low	Exhaust Gas Recirculation Sensor B Circuit High

Is the fuel pump sometimes not priming when you turn the key to ON(II)? Start by measuring the fuel pressure and checking whether you have bright white-bluish spark at all four plugs. The mechanical timing is also something that you should check, as we mentioned above.

U0123 OBD-II Diagnostic Network (U) Trouble Code Description

U0123 engine trouble code is about Exhaust Gas Recirculation Sensor B Circuit High.

Main reason For U0123 Code

The reason of U0123 OBD-II Engine Trouble Code is Fuel Rail/System Pressure - Too High.

Parts or components should not be replaced with reference to only a U0123 DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

	Example: 0140