Air conditioning system pressure diagnosis

What should you do before starting any service on an air conditioning system?

• Check the weather forecast

• Consult local authorities for licensing requirements

• Buy new refrigerant

• Turn off the vehicle

What might a high reading on both gauges with no fluctuation indicate?

• Low refrigerant charge

• A faulty compressor

• Air and moisture in the system

• A blocked condenser

If the low side gauge shows low to vacuum and the high side is also low, what should you check for?

• Ice build-up on the high side

• Frost build-up on low pressure pipes

• A stuck expansion valve

• A faulty thermistor

What might cause both pressure gauges to display higher than normal values?

• Low refrigerant charge

• A faulty compressor

• A leaking component

• A jammed thermal expansion valve

What is a useful diagnostic aid for identifying blockages in an air conditioning system?

• The visual test

• The smell test

• The sound test

• The touch test