AC system recharge on a 2024 Tesla Model 3 Performance using R-1234yf refrigerant. This Tesla uses a heat pump system shared with the cabin and battery thermal loop — recharge work is limited to the AC service ports only; do not open or service the octovalve or refrigerant lines connected to battery thermal components.

Warnings

Tools required

Parts

• R-1234yf refrigerant × 1 — SAE J2845 certified R-1234yf
• PAG oil compatible with R-1234yf and electric AC compressors (non-conductive, manufacturer-specified) × 1 — Electric-compressor-rated POE/PAG oil per Tesla Service Manual — DO NOT use standard PAG
• Service port valve cores (if leak found) × 2 — R-1234yf high/low side cores
• Service port caps with seals × 2 — OEM replacement

Preparation

1. TESLA SAFETY PREAMBLE: Park on level ground, place in P, engage the parking brake.
2. Exit all doors with the key fob/phone key carried well away from the vehicle. Wait at least 2 minutes for HV systems to fully de-energize, even on this non-HV job.
3. Open the front trunk and disconnect the 12V (or Li-ion low-voltage) battery. On 2024 Model 3 Performance the LV battery may be the lithium unit located per architecture notes — confirm location before disconnecting and follow Tesla's documented LV disconnect sequence.
4. DO NOT touch, cut, or pierce ANY orange cable — these are high-voltage and lethal.
5. If at any point you encounter an orange cable, an HV component, or are unsure if a system is de-energized: STOP and consult a Tesla-certified technician.
6. Confirm refrigerant type from the underhood AC service label (R-1234yf) and note the specified charge weight in grams.
7. Allow the vehicle to sit with HVAC off for at least 10 minutes so refrigerant pressure equalizes before attaching gauges.
8. Locate the AC high-side and low-side service ports in the front trunk (frunk) area; remove the service port caps.
9. Verify refrigerant purity at the low-side port using a refrigerant identifier before connecting the recovery machine.

Procedure

1. 1

   Identify refrigerant
   Connect a refrigerant identifier to the low-side service port. Confirm the system contains pure R-1234yf. If the identifier reports air contamination >2% or the presence of R-134a/hydrocarbons, stop — the system requires recovery into a contaminated-refrigerant tank and further diagnosis.
   ⚠Contaminated refrigerant will damage your recovery machine and void any future Tesla warranty claim on the AC system.
2. 2

   Connect R-1234yf recovery/recharge machine
   With the machine OFF and valves closed, connect the high-side and low-side couplers to the corresponding service ports. Verify both couplers latch fully. Turn the machine on and let it read static pressures. Record both pressures — abnormally low or zero indicates a leak that must be found before recharging.
3. 3

   Recover existing refrigerant
   Run the machine's recovery cycle until system pressure reaches and holds the machine's recovery vacuum threshold. Record the recovered weight in grams. Compare to the label's full-charge spec — a significant shortfall confirms a leak.
4. 4

   Optional leak check (if recovered charge was low)
   If recovered weight was less than ~80% of the spec, perform a leak test: pressurize with dry nitrogen to a safe test pressure per the manufacturer-specified procedure, or use the vacuum decay test in step 5 combined with an electronic leak detector. Common leak points on Model 3 are the front condenser (stone damage), service port valve cores, and accessible line fittings in the frunk. Do NOT chase leaks into the heat-pump/octovalve assembly — that is dealer-only service.
   ⚠️If a leak is suspected at any line connecting to the octovalve or heat-pump module, STOP and refer to a Tesla service center.
5. 5

   Evacuate the system
   Pull a deep vacuum using the machine's vacuum cycle for a minimum of 30 minutes (longer if ambient humidity is high), targeting 500 microns or lower. After reaching target, close valves and perform a vacuum decay/hold test for at least 5 minutes. Pressure rise indicates moisture or a leak — re-evacuate or diagnose before proceeding.
6. 6

   Add PAG/POE oil if required
   If the system was opened or oil was lost during recovery (machine reports recovered oil volume), inject the equivalent volume of electric-compressor-rated oil specified by Tesla. For a simple recharge with no service performed, no oil addition is typically required. NEVER substitute generic PAG oil — it is conductive and will damage the high-voltage electric compressor.
   ⚠️Wrong oil = HV short in the compressor windings. Verify the oil bottle is explicitly rated for electric/hybrid AC compressors.
7. 7

   Charge to specified weight
   Program the recharge machine with the exact charge weight (in grams) listed on the underhood AC service label. Run the charge cycle. Allow the machine to fully transfer the programmed weight. Do not 'top up' by pressure — electric heat-pump systems are charge-weight critical.
8. 8

   Disconnect couplers and inspect ports
   Close machine valves, run the coupler purge cycle, and disconnect from the service ports. Inspect each service port for refrigerant weep — a small amount of oil residue indicates a valve core leak. Replace cores and caps as needed. Install service port caps (with seals) finger-tight plus a snug turn — these caps are the system's secondary seal.
9. 9

   Reconnect 12V/LV battery
   Reconnect the low-voltage battery following the Tesla-documented reconnect sequence. Close the frunk. Wake the vehicle and allow it to complete its boot/self-check cycle (typically 30–60 seconds) before operating HVAC.
10. 10

    Functional test
    Start the vehicle, set HVAC to MAX A/C, lowest temperature, highest fan, recirculation ON. Allow 5 minutes to stabilize. Measure center-vent outlet temperature with a thermometer — expected output in moderate ambient (~21–27°C / 70–80°F) is roughly 4–8°C / 40–46°F. Use the Tesla touchscreen Service menu (if accessible without Toolbox) to view AC pressures; otherwise verify via gauge readings during the recharge cycle. Listen for compressor cycling abnormalities.
    ℹ️The heat pump may briefly run reversing/defrost cycles on first startup — this is normal.

Reassembly

1. Confirm both AC service port caps are installed with intact O-rings.
2. Verify no tools or rags are left in the frunk.
3. Close the frunk and confirm the latch engages fully.
4. Clear any HVAC-related alerts from the touchscreen if present after the post-service drive.

Verification

• Center-vent temperature drops to the expected range within 5 minutes of MAX A/C operation.
• No HVAC, refrigerant pressure, or compressor fault alerts on the Tesla touchscreen after a 10-minute drive cycle.
• Vacuum decay test held during the procedure (no pressure rise over 5 minutes at 500 microns).
• Recharge weight delivered matches the underhood label spec within machine tolerance.
• No audible compressor knocking or surging during cabin cooling or battery preconditioning.
• While AC service is not on a fixed Tesla interval, take this opportunity to check the cabin air filter — Tesla recommends replacement every 2 years on Model 3.

More procedures for this vehicle