Volkswagen Jetta Sportwagen U0121 Engine Error Code

When you check Volkswagen Jetta Sportwagen car engine light came on code U0121 the reason should be Engine Light ON (or Service Engine Soon Warning Light). However Volkswagen manufacturer may have a different definition for the U0121 OBD-II Diagnostic Network (U) Trouble Code. So you should chech it on our car models.

Another consequence of U0121 Volkswagen Jetta Sportwagen engine overheating may be a blown head gasket. Heat makes aluminum swell almost three times faster than cast iron. Thermal stress can distort the head and make it swell in areas that are hottest like those between exhaust valves in adjoining cylinders, and areas that have restricted coolant flow like the narrow area that separates the cylinders. The typical aluminum head swells most in the middle, which can crush the head gasket if the head gets too hot. This will usually cause the head gasket to leak compression between adjacent cylinders, or leak coolant into the cylinders.

Volkswagen Jetta Sportwagen U0121 OBD-II Diagnostic Network (U) Trouble Code Description Volkswagen Jetta Sportwagen car U0121 OBD-II Trouble Code Modules connected to the high speed General Motor Local Area Network (GMLAN) serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and comm Reason For Volkswagen Jetta Sportwagen U0121 Code The reason of Volkswagen Jetta Sportwagen U0121 OBD-II Engine Error Code is U0121 Lost Communication With Electronic Brake Control Module.

There are currently two main types of cylinder deactivation used today, depending on the type of engine. U0121 Volkswagen Jetta Sportwagen code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.

Volkswagen Jetta Sportwagen U0121 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.

What does fault code U0121 mean for Volkswagen Jetta Sportwagen ? What does a diagnostic reading U0121 mean for Volkswagen Jetta Sportwagen ? How to fix OBD2 Code U0121 for Volkswagen Jetta Sportwagen ? What do we know about U0121 code for Volkswagen Jetta Sportwagen ?