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Checking Procedure

WARNING: This page is about a different car, the 2004 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette smoke in the vicinity of the vehicle. Perform the leak test in a calm area (low air/wind movement) so that the leaking refrigerant is not dispersed.
  1. Turn the engine OFF.
  2. Connect the manifold gauge set (J-39183-C) to the A/C service ports. Refer to SETTING OF SERVICE TOOLS AND EQUIPMENT .
  3. Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm2 , 50 psi) above a temperature of 16°C (61°F). If less than specification, recover/evacuate and recharge the system with the specified amount of refrigerant. Refer to HFC-134A (R-134A) SERVICE PROCEDURE .
    NOTE: At temperatures below 16°C (61°F), leaks may not be detected since the system may not reach 345 kPa (3.54 kg/cm2 , 50 psi) pressure.
  4. Conduct the leak test from the high pressure side (compressor discharge to evaporator inlet) to the low pressure side (evaporator drain hose to shaft seal). Refer to COMPONENTS . Clean the component to be checked and carefully move the electronic refrigerant leak detector probe completely around the following connections and components.
    • Compressor
    • High and low-pressure pipe and hose fittings, relief valve, and compressor shaft seal
    • Liquid tank
    • Refrigerant pressure sensor
    • Service valves. Check all around the service valves. Ensure service valve caps are secured on the service valves (to prevent leaks).
      NOTE: After removing manifold gauge set (J-39183-C) from the service valves, wipe any residue from the service valves to prevent any false readings by the electronic refrigerant leak detector (J-41995).
    • Evaporator

    With engine OFF, turn blower fan on "High" for at least 15 seconds to dissipate any refrigerant trace in the heater and cooling unit assembly. Wait a minimum of 10 minutes accumulation time (refer to the manufacturer's recommended procedure for actual wait time) before inserting the electronic refrigerant leak detector probe into the heater and cooling unit assembly drain hose.

    NOTE: Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water or dirt that may be in the drain hose.
  5. If a leak is detected, verify at least once by blowing compressed air into the area of the suspected leak, then repeat the leak check.
  6. Do not stop when one leak is found. Continue to check for additional leaks at all system components and connections.
  7. If no leaks are found, perform steps 8 -11.
  8. Start the engine.
  9. Set the heater A/C controls as follows:
    NOTE: For the automatic system, turn OFF the automatic controls and set the heater A/C controls manually.
    1. A/C switch to ON
    2. Air flow to VENT mode
    3. Intake position to RECIRCULATION mode
    4. Temperature to MAX cold
    5. Fan speed to HIGH
  10. Run the engine at 1,500 RPM for at least 2 minutes.
  11. Turn the engine OFF and perform the leak check again following steps 4 through 6 above.

    Refrigerant leaks should be checked immediately after turning the engine OFF. Begin with the leak detector at the compressor. The pressure on the high pressure side will gradually drop after the refrigerant circulation stops and pressure on the low pressure side will gradually rise, as shown in Fig 1. Some leaks are more easily detected when the pressure is high.

    Fig 1: Pressure Graph
    G00342210Courtesy of NISSAN MOTOR CO., U.S.A.
  12. Before connecting the recovery/recycling recharging equipment (ACR2000) (J-43600) to the vehicle, check the recovery/recycling recharging equipment (ACR2000) (J-43600) gauges. No refrigerant pressure should be displayed. If pressure is displayed, recover the refrigerant from the equipment lines and then check the refrigerant purity.
  13. Confirm refrigerant purity in supply tank using recovery/recycling recharging equipment (ACR2000) (J-43600) and refrigerant identifier equipment (J-41810-NI).
  14. Confirm the refrigerant purity in the vehicle's A/C system using recovery/recycling recharging equipment (ACR2000) (J-43600) and refrigerant identifier equipment (J-41810-NI).
  15. Discharge the A/C system using recovery/recycling recharging equipment (ACR2000) (J-43600). Repair the leaking fitting or component as necessary.
  16. Evacuate and recharge the A/C system and perform the leak test to confirm that there are no refrigerant leaks.
  17. Conduct the Operational Check to ensure system works properly. Refer to OPERATIONAL CHECK .
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