Leak Test
- Position the vehicle in a wind-free work area. This will aid in detecting small leaks.
- Operate the heating and A/C system with the engine at idle under the following conditions for at least 15 minutes.
- Doors or windows open
- Transmission in Park or Neutral with the parking brake set (depending on transmission application)
- Front A/C and heater controls set to outside air, full cool, panel mode, high blower and A/C compressor engaged
- If equipped, rear A/C and heater controls set to full cool and high blower.
- Shut the vehicle off and wait at least 5 minutes.CAUTION:
Use it is important to use only a high-quality Ultra Violet (UV) light when searching for a leak in the refrigerant system. Small leaks may not be found using budget equipment. Failure to follow these instructions may result in an incomplete diagnosis and possible remaining refrigerant leaks.
- Begin searching for leaks using a high quality UV light to detect the fluorescent R-134a leak detection dye. Inspect all connections, plumbing fittings, brazed joints, hoses, hose crimps, service ports, compressor housing, pressure relief valve and A/C condenser for dye. Inspect the evaporator drain tube and condensate for presence of dye, which indicates a leak from the A/C evaporator.WARNING:
Use extreme care when working around a running engine. Keep hands and fingers clear of the radiator fan, accessory drive belt and all other moving components. Keep away when wearing loose clothing, jewelry or long hair that is not properly secured. Underhood components may become hot to the touch. Be careful not to come into contact with hot engine, A/C and engine cooling system components. Failure to follow these instructions may result in serious or fatal injury.
CAUTION:Use only an electronic leak detector designed for R-134a refrigerant. It is important to use only high-quality refrigerant leak detection equipment. Small leaks may not be found using budget equipment. Failure to follow these instructions may result in an incomplete diagnosis and possible remaining refrigerant leaks.
- If a leak is not found with the R-134a detection dye, use a high-quality electronic R-134a leak detector and insert it into the evaporator drain tube, and into the instrument panel air outlets, to check for evaporator leaks. Check the evaporator tubes at the A/C expansion valve, for leaks not visible behind the valve. Check around the front of the A/C compressor, for compressor shaft seal leaks. Check between the A/C condenser and radiator for condenser leaks not previously visible.