AC High Pressure Switch

This procedure replaces the AC high pressure switch on the 2023 Chevrolet Bolt EUV electric vehicle, requiring AC system discharge and recharge.

Warnings

Tools required

Parts

• AC high pressure switch × 1 — Use OEM specification
• AC line O-rings × 2 — Use OEM specification
• PAG oil for AC system × 1 — GM approved PAG oil

Preparation

1. Park vehicle on level surface and apply parking brake
2. Ensure AC system has been off for at least 10 minutes to equalize pressures
3. Connect AC recovery machine and fully recover all R-1234yf refrigerant from the system following EPA-approved procedures
4. Document refrigerant quantity recovered for proper recharge amount
5. Disconnect 12V negative battery cable and wait 2 minutes
6. Locate the AC high pressure switch on the high pressure line near the condenser in the front of the vehicle

Procedure

1. 1

   Access the high pressure switch
   Remove any plastic covers or shields blocking access to the AC high pressure switch located on the high pressure liquid line near the condenser. The switch is typically positioned on the line between the condenser outlet and the thermal expansion valve.
2. 2

   Disconnect electrical connector
   Press the locking tab on the high pressure switch electrical connector and carefully pull the connector straight off the switch. Use an electrical connector removal tool if the connector is tight. Inspect the connector for corrosion or damage.
3. 3

   Remove the high pressure switch
   Using a 10mm wrench or socket, carefully unscrew the high pressure switch from the AC line fitting. Turn counterclockwise to remove. Some residual refrigerant or oil may escape. Have shop towels ready to catch any drips.
4. 4

   Inspect and clean fitting
   Inspect the threaded port on the AC line for damage or debris. Clean the threads and sealing surface with a lint-free shop towel. Check for any signs of corrosion or cross-threading that would prevent proper sealing.
5. 5

   Prepare new switch
   Remove the new AC high pressure switch from packaging. Verify it matches the original part. Install new O-rings on the switch if not pre-installed. Apply a small amount of clean PAG oil to the O-rings to aid installation and ensure proper sealing.
6. 6

   Install new high pressure switch
   Thread the new high pressure switch into the AC line port by hand, turning clockwise. Ensure it threads smoothly without resistance. Once hand-tight, use a torque wrench to tighten to specification.
   Torque spec

   AC Line Fittings20 Nm (15 lb-ft)
7. 7

   Reconnect electrical connector
   Push the electrical connector onto the new high pressure switch until it clicks into place. Ensure the locking tab is fully engaged. Gently tug on the connector to verify it is securely attached.
8. 8

   Reinstall covers
   Reinstall any plastic covers or shields that were removed for access. Ensure all fasteners are properly secured and no wiring is pinched.
9. 9

   Vacuum and recharge AC system
   Connect AC service equipment. Pull a vacuum on the system for at least 30 minutes to remove all air and moisture. Monitor vacuum gauge to ensure system holds vacuum, indicating no leaks. Recharge the system with the documented amount of R-1234yf refrigerant using approved equipment.
10. 10

    Reconnect battery and test
    Reconnect the 12V negative battery cable. Start the vehicle and turn on the AC system. Allow it to run for 5 minutes while monitoring pressures. Verify the high pressure switch is functioning properly and there are no refrigerant leaks at the switch location using a leak detector.

Reassembly

1. Ensure all electrical connectors are fully seated and locked
2. Verify all access covers and shields are reinstalled
3. Confirm AC system pressures are within normal operating range (typically 200-250 psi on high side at idle)
4. Document refrigerant amount added and any system observations

Verification

• Start vehicle and set AC to maximum cooling with blower on high
• Verify cold air is being produced from vents within 2-3 minutes
• Use AC leak detector around the high pressure switch connection - no leaks should be detected
• Monitor AC system pressures with gauges to ensure they are within specification
• Verify high pressure switch electrical connector is secure and properly locked
• Scan for diagnostic trouble codes - no AC system codes should be present
• Test AC operation in various temperature settings to ensure proper cycling

Related trouble codes on this vehicle

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