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P0421 Engine Diagnostic Code For Bmw 535d Xdrive

Sample P0421 Engine

P0421 engine code for Bmw 535d Xdrive provides below are generic codes that may not apply to all vehicles. Bmw 535d Xdrive manufacturer uses specific Bmw 535d Xdrive diagnostic code that are different from the codes shown below. Foreign vehicles may also use DTC codes different from the generic DTC codes.

On 1999 and later P0421 engines, the instrument cluster has a built-in self-diagnostic mode that can be accessed by pressing and holding the instrument cluster SELECT/RESET button. Insert the ignition key and turn to the RUN position (but don't crank or start engine). Continue to press and hold the SELECT/RESET button (for 5 seconds) until the word TEST is displayed by the odometer. Release the SELECT/RESET button within three seconds after the word TEST is displayed to begin the self-diagnostic mode.

P0421 Diagnostic Trouble Code For Bmw 535d Xdrive Meaning

P 0 4 21
Powertrain Problem SAE - Generic Auxiliary Emission Controls 21 Engine Fault Code
Bmw 535d Xdrive Car Engine How to fix P0421 engine diagnostic code For Bmw 535d Xdrive ?

Starting letter P diagnostic code shows that there are problems in engine, transmission and emissions systems.
If your "Check Engine Light" is on, it means your vehicle has one or more OBD II Trouble Codes so you have to check your engine diagnostic code tool.

If your vehicle is an older model with a non-electronic Auxiliary Emission Controls, you can check the distributor cap to see whether the spark is getting from there to the coil and on to the spark plugs.


Don't forget ! If your P0421 engine code not resolved on and there are trouble codes in your computer, your vehicle will not pass an OBD 2 emissions test. The light must be off and there must be no codes in memory to pass an OBD 2 emissions test. In addition, all of the OBD II self-monitors that check for faults must have run and completed without finding any further problems to pass the test.