Can you be arrested for car repossession?

It would depend on local law; generally repossession is done after forfeiture on the loan on that car, or as part of a general claim on a person's property (to pay of debts or a fine, for instance). If such laws are not in place locally, or the rules aren't followed, repossession would still be theft.

In America, in general, repossession is done by repo men, and they are allowed to repossess objects used as the object of a loan, as long as they announce the repossession to the (former) owner. The reason many TV shows about repo men show them as being careful and "ready for anything" is because being legally right is little consolation if you are physically assaulted or even killed in the process.