Automotive repossession happens when you fail to pay your car payments on time. Usually, your bank will contact you via letter to notify you that you're late on your payments. Next, your bank will call you to ask if you're going to pay the money you owe and notify you of the threat that your vehicle will be repossessed. Following a predetermined grace period, the bank will then contact a repossession service and put in an order for the repossession of your vehicle.
Next, your vehicle will get repossessed. They won't call you and tell you when it's going to happen, it will just happen as soon as they find your car out in the open where the repo man can hook up the tow truck. After the repossession happens, you'll receive a letter detailing how much you owe in repossession fees and outstanding loan payments.
This, of course, is what happens if you don't do anything to fix your late payments. Before the repossession process is underway, you may have opportunities to call and negotiate a solution with your lender. The earlier you call your lender to negotiate the easier time you'll have. Since most lenders see repossession as a last resort, they may be willing to work with you by letting you skip one or two payments or by spreading the amount you owe across several months.
Other solutions might be to refinance your car, negotiate a loan modification, sell your car and pay off your loan with the money you receive and many other solutions. Ultimately, if no solution exists that fits your situation, you may be able to file for bankruptcy -- which could delay the repossession of your vehicle and help you keep it.