This engine P1543 Code is found in many car engines and by the description, the problem of the car engine can be known. Here the problem is PATS anti-theft system and this problem can be solved by an trusted and experienced automobile engineer. Do not try to solve the car engine any immature automobile engineer who make more terrible problem in the car engine. The engine of the car can be solved easily if an expert automobile engineer fix the car engine. If you know how to fix the car engine and you have all necessary tools, you can try to fix the car engine.