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Recently, I encountered the following trouble codes; nevertheless, I did not see any alterations when driving.

P0123 "Throttle/accelerator pedal position sensor circuit A high voltage"
P2112 "Throttle Actuator A Control System - Stagnant"


I researched more and found on a forum that resetting the throttle body may be beneficial.

Subsequent to the reset, the vehicle fails to initiate. The engine cranks but fails to ignite; sometimes, the RPM briefly increases, suggesting potential ignition, but it promptly declines again. I attempted the reset several more times without success.

My vehicle is a 2011 Mercedes W204 C220 CDI equipped with an OM651.911 engine.

What may this pertain to? Thank you in anticipation!

What method did you use to reset the throttle body?

Depressing the accelerator pedal fully while the ignition is in position II does not reset any systems; rather, it deceives the vehicle into believing it is being driven aggressively, prompting it to initiate adaptive responses. It is unlikely that this would prevent the automobile from starting, except


It seems there is a malfunction with a sensor. It is advisable to have it evaluated by an expert equipped with access to Mercedes' diagnostic systems, referred to as STAR.

What actions were necessary to restore functionality to your vehicle? I am experiencing the same problem.

Have you cleaned the body prior to the reset? There is no need in resetting a soiled body, since the plate cannot seal correctly with debris present.

Assuming it is the C220 CDI in your sidebar, it does not possess a throttle, similar to other CDI vehicles. The component resembling a throttle is an anti-shudder valve (also known as a shutdown valve), which remains mostly completely open throughout engine operation, but may partly close to assist with EGR airflow under certain situations. Engine revolutions are not regulated by it; with a direct injection engine, revolutions are solely controlled by injector pressure and duration. Certain tuners entirely eliminate them; however, I would advise against this, since it results in an unpleasant, irregular thud upon shutdown and heightens the risk of engine runaway if oil is inadvertently overfilled.

Unsavoury matters attributed to the devil valve.

That will not facilitate airflow; nevertheless, it will not prevent initiation. There must be a significant amount of oil circulating through the turbo for it to be that detrimental. On my last ALFA, it was very clean; I installed a catch tank, and the EGR input was positioned beyond that valve.

Undoubtedly a significant VAG issue.

That is pristine.