Brake system service is perhaps the most crucial aspect of vehicle service. If the engine won’t start, the customer is stranded. If the engine or transmission causes a surge or poor acceleration, the customer is annoyed. But if the vehicle won’t stop, that’s a big problem.
Many technicians start to feel uncomfortable about a diagnostic situation if the scanner only shows U-codes, but if the scanner powers up but will not communicate, that uncomfortable feeling intensifies.
During the past three or four decades, the basic theory of the automotive air conditioning system hasn’t changed a whole lot. What has changed is everything else that’s part of a vehicle’s air conditioning system.
