volvospeed has a listing of your engine codes. They mean that the ECU has detected a fault in one or more of the many sensors/components of the engine management system. They may or may not require attention. I'd check out what they mean and then clear them and see if they return.

Check your tires. May be you only need to replace two for now keeping the best two on and do them several months down the road when your $$ increase. You don't want to risk a tire failure.

bl