Honda Pilot: A/C Refrigerant Leak Check

Honda Pilot 2016-2022 (YF5/YF6) Service Manual / Remove, Install, Replace, Check info / A/C Refrigerant Leak Check

Check

WARNING

Compressed air mixed with the HFO-1234yf (R-1234yf)forms a combustible vapor.
The vapor can burn or explode causing serious injury.
Never use compressed air to pressure test HFO-1234yf (R-1234yf) service equipment or vehicle air conditioning systems.

CAUTION

Air conditioning refrigerant or lubricant vapor can irritate your eyes, nose, or throat.
Be careful when connecting service equipment.
Do not breathe refrigerant or vapor.

NOTE:

If accidental system discharge occurs, ventilate the work area before resuming service.
Additional health and safety information may be obtained from the refrigerant and lubricant manufacturers.
Check the system for leaks using an R-1234yf refrigerant leak detector with an accuracy of 14 g (0.49 oz) per year or better.

1. A/C Recover/Recycle/Recharge Machine - Connect

2. A/C Refrigerant - Recover

3. A/C System - Evacuate

4. A/C Refrigerant - Charge

5. A/C Refrigerant - Leak Check

With the power system off, use a leak detector first to detect the leak source. Follow a continuous path in order to ensure that you will not miss any possible leaks. Test the following areas of the system for leaks:

Possible Leak Area	Diagnostic Procedure with the Leak Detector	Notes
Service ports	Check the service ports with caps installed Use an electronic leak detector.	When capping the service ports, ensure that the seals on the port caps are in place, and that the caps are tight. The caps are used as the final seals in the system
A/C condenser	Use the leak detector or a POE based leak dye.	Check for joints or connections coated with oily dust Check for damaged and corroded areas Check all fittings, couplings, brazed/welded areas and areas around attachment points Move the probe slowly (1 in./second or less), and keep it within 1/4 in. of the component being checked. This maximizes the chance of detecting a leak If you detect a leak, blow compressed air over the area, then recheck for leaks. For large leaks, cleaning the area with compressed air may help you pinpoint the leak source
Evaporator	Check at the evaporator drain hose Check at the passenger's side vent and turn the blower on at low speed
A/C lines	Wiggle the rubber hoses when checking crimped metal ends Use the leak detector or a POE based leak dye.	Check all fittings, couplings, pressure switches, brazed/welded areas, and areas around attachment points on A/C lines and components Check for damaged and corroded areas Move the probe slowly (1 in./second or less), and keep it within 1/4 in. of the component being checked. This maximizes the chance of detecting a leak

If a leak could not be found with the detector, do the following: close the quick coupler valves, then disconnect the quick couplers from the vehicle service ports.
Attach the dye kit hose/coupler, a new dye cartridge and EZ-Ject plunger to the service valve fitting (see the manufacturer's instructions for more detail).
Turn the plunger clockwise to inject the dye.
Remove the dye kit hose/coupler, dye cartridge and EZ-Ject plunger from the service valve fitting.
Start the engine, and set the A/C system to maximum cooling. Open the control valve to let refrigerant and the dye enter the A/C system through the low pressure service port. Close the control valve when the dye capsule is empty.
Run the A/C system for 15 minutes to thoroughly circulate the dye. Then shut the power system off, and inspect the following areas of the system for leaks.

NOTE:

Check for leaks in a dark work area, and use the UV light and the special glasses from the leak check kit. Other UV lights may not work well.
Small leaks may take up to 1 week of vehicle operation (with normal A/C use to become visible.

Possible Leak Area	Diagnostic Procedure with Infrared Leak Detector or Fluorescent Dye
Service ports	If a leak is found, replace the cap/O-ring seal or A/C line as needed
A/C lines	Use a permanent marker pen to circle the leak area If a leak is found, remove and replace the A/C line
A/C condenser	If a leak is found, remove the A/C condenser Determine whether leak is in the A/C condenser or the receiver/dryer Use a permanent marker pen to circle the leak area Replace either the receiver/dryer, desiccant or the A/C condenser, depending upon which is leaking
A/C compressor	Check for leaks at all of the A/C compressor joints, the A/C compressor front housing bolts, and the scroll bolts on the back of the A/C compressor If a leak is found, use a permanent marker pen to circle the leak area If the A/C compressor relief valve appears to be leaking, determine whether the leak is coming from the relief valve, or the joint between the A/C compressor casing and the valve. If the leak is from the relief valve, check the A/C system pressures, and refer to the pressure test table in the A/C system test. If the leak is from the casing/valve joint, replace the A/C compressor relief valve If the leak is coming from the suction hose and/or discharge hose fittings on the A/C compressor, clean the A/C fittings and replace the suction/discharge fitting O-rings For all other A/C compressor leaks, remove and replace the A/C compressor
Evaporator	Start checking for evaporator leaks by illuminating the evaporator drain tube area If a leak is found, remove the evaporator core Determine whether leak is from evaporator or expansion valve Use a permanent marker pen to circle leak area Replace the expansion valve or the evaporator core, depending upon which is leaking