Hello, I have 2007 isuzu npr, the check engine light came up, last time I have to take it in to the dealer to have it fixed. Can I do it myself? I know it has to do with the DPFor DFP regeneration. Thanks

As with any CEL the code needs to be read using a code reader or the on board system. Once that is done you need to determine what the cause/causes could be. Then it is simply a matter of fixing the offending problem.