This procedure involves replacing the AC low pressure switch on a 2024 Rivian EDV 500, which monitors refrigerant pressure in the air conditioning system and requires refrigerant recovery and evacuation.

Warnings

Tools required

Parts

• AC low pressure switch × 1 — Use OEM specification
• O-ring seal kit for AC lines × 1 — Use OEM specification
• R-1234yf refrigerant × 1 — As needed per system capacity
• PAG oil for electric vehicle AC compressor × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Turn off vehicle and remove key/disconnect mobile key
3. Allow AC system to sit for at least 30 minutes after last operation to equalize pressures
4. Verify you have proper EPA Section 609 certification for mobile AC work
5. Ensure AC recovery machine is certified for R-1234yf and has been properly maintained
6. Confirm refrigerant identifier shows pure R-1234yf in the system before recovery
7. Open all doors and windows for ventilation during refrigerant recovery
8. Document pre-repair AC system performance if possible

Procedure

1. 1

   Disable high-voltage system
   Follow Rivian service procedures to disable the high-voltage system. Access the service disconnect located in the front cargo area. Remove the service disconnect cover and pull the service disconnect lever to the OFF position. Wait 5 minutes for capacitors to discharge. Verify system is de-energized using appropriate high-voltage test equipment.
2. 2

   Disconnect 12V battery
   Disconnect the negative terminal of the 12V auxiliary battery located in the front storage compartment. Wait 2 minutes for all vehicle systems to fully power down. This prevents electrical faults during switch replacement.
3. 3

   Access the AC low pressure switch
   The AC low pressure switch is located on the suction line near the AC evaporator, accessible from the front passenger side of the vehicle. Remove the front passenger wheel well liner by removing the plastic fasteners. You may need to turn the steering wheel fully left for better access. The switch is mounted on the larger diameter AC line (suction side) with an electrical connector.
4. 4

   Connect recovery equipment
   Connect the AC manifold gauge set to the AC service ports. The low-pressure port is on the larger suction line (blue cap), and high-pressure port is on the smaller liquid line (red cap). Ensure all connections are secure and gauges read system pressure. Note the static pressure reading for later reference.
5. 5

   Recover AC refrigerant
   Connect the AC recovery machine to the manifold gauge set. Start the recovery process according to machine manufacturer instructions. Monitor the recovery process - it typically takes 20-30 minutes. Continue recovery until gauges read below 0 PSI (vacuum) and machine indicates recovery is complete. The machine will capture both refrigerant and compressor oil. Note the amount of oil recovered for replacement during recharge.
6. 6

   Disconnect AC low pressure switch
   Once system pressure is at 0 PSI, disconnect the electrical connector from the AC low pressure switch by pressing the release tab. Label or photograph the connector orientation. Clean the area around the switch to prevent contamination from entering the AC system.
7. 7

   Remove AC low pressure switch
   Using an appropriate wrench, carefully unthread the AC low pressure switch from the AC line fitting. Be prepared for a small amount of residual refrigerant or oil to escape. Remove the switch and immediately cap or plug the opening in the AC line to prevent moisture and contamination from entering the system. Inspect the O-ring seal for damage.
8. 8

   Prepare new AC low pressure switch
   Remove the new AC low pressure switch from its packaging. Check that it matches the original part. Lubricate the new O-ring seal with a small amount of PAG oil compatible with EV AC systems. Do not use petroleum-based lubricants. Ensure the threads are clean and undamaged.
9. 9

   Install new AC low pressure switch
   Remove the cap/plug from the AC line. Thread the new AC low pressure switch into the AC line fitting by hand to avoid cross-threading. Once hand-tight, use a torque wrench to tighten the switch. Without specific torque specifications, tighten to snug plus 1/4 turn, being careful not to overtighten and damage the aluminum AC line threads. The switch should be secure without excessive force.
10. 10

    Reconnect electrical connector
    Reconnect the electrical connector to the new AC low pressure switch. Ensure the connector clicks securely into place and the locking tab is fully engaged. Verify the seal on the connector is properly seated to prevent moisture intrusion.
11. 11

    Evacuate AC system
    Connect the AC vacuum pump to the manifold gauge set. Open the appropriate valves and start the vacuum pump. Evacuate the AC system to at least 29 inches of mercury (500 microns if using a micron gauge). Continue evacuation for a minimum of 45 minutes to remove all moisture and air. After evacuation, close valves and shut off pump. Monitor vacuum for 10 minutes - if vacuum holds steady, system is leak-free and ready for recharge.
12. 12

    Recharge AC system
    Using R-1234yf refrigerant only, recharge the AC system to the capacity specified on the vehicle's underhood label (typically 1.5-2.0 lbs for this system). Add PAG oil to compensate for the amount removed during recovery, plus 1 oz for the new switch. Use the recovery machine's built-in charging function or a dedicated charging station. Charge refrigerant into the low-pressure side with the vehicle off. Monitor gauge pressures during charging.
13. 13

    Reconnect 12V battery and enable high-voltage system
    Reconnect the negative terminal of the 12V auxiliary battery. Return to the front cargo area and push the high-voltage service disconnect lever to the ON position. Replace the service disconnect cover. Wait for vehicle systems to initialize.
14. 14

    Test AC system operation
    Power on the vehicle. Set the AC to maximum cooling with maximum fan speed. Allow the AC to run for at least 10 minutes. Monitor gauge pressures - typical operating pressures should be 25-45 PSI on low side and 150-250 PSI on high side at idle (varies with ambient temperature). Verify the AC low pressure switch is functioning by checking for proper compressor cycling. Use the digital multimeter to verify switch operation if needed.
15. 15

    Perform leak check and finalize
    Using an electronic leak detector designed for R-1234yf, check all AC line connections, the new pressure switch, and service ports for leaks. Pay special attention to the pressure switch installation point. If no leaks are detected, disconnect the manifold gauge set and install caps on service ports. Reinstall the wheel well liner and any removed trim panels. Clear any diagnostic trouble codes using Rivian diagnostic software if available.

Reassembly

1. Reinstall all trim panels and wheel well liner components removed during access
2. Ensure all electrical connectors are properly secured with locking tabs engaged
3. Install protective caps on AC service ports to prevent contamination
4. Verify no tools or parts are left in the engine compartment or wheel well area

Verification

• Start vehicle and verify AC system cools effectively with no unusual noises
• Monitor AC pressures with gauge set - low side should be 25-45 PSI, high side 150-250 PSI at idle (ambient dependent)
• Verify AC compressor cycles properly based on pressure switch operation
• Check for proper air temperature at vents - should be 40-50°F colder than ambient
• Scan for diagnostic trouble codes related to AC system - there should be none
• Perform electronic leak check around new pressure switch installation - no leaks should be present
• Verify proper operation of automatic climate control functions
• Test drive vehicle and confirm AC performance under various conditions

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