Tesla Model 3: Heat pump refrigerant line fitting corrosion

The aluminium refrigerant line fittings connecting the heat pump circuit corrode at the junction with the steel firewall bracket, causing progressive refrigerant loss. Affected vehicles lose cabin heating and show reduced range in cold weather. Tesla issued a service bulletin and has replaced fittings under warranty on some vehicles. The fault worsens over time — small leaks become total refrigerant loss if left unaddressed.

• Loss of cabin heat in cold weather
• Reduced driving range in winter conditions
• HVAC system blowing cold or ambient air only
• Climate or thermal management warning on touchscreen

1. 1

   Verify heat pump operation by running climate heat in cold mode and checking outlet temperature.

2. 2

   Look for refrigerant leak dye or prior service evidence around firewall fittings.

3. 3

   Confirm any warranty claims or service bulletins applied.

Parts involved: Body corrosion.

$1,200 to $3,500 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

• “Has cabin heating worked reliably every winter since purchase?”
• “Has the refrigerant system or heat pump been serviced or topped up?”
• “Have any Tesla service bulletins relating to heating been applied?”

The failure described above is documented in published sources — owner forums, technical service bulletins, recall notices and workshop write-ups — held in our fault database. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them, and it is a starting point for an inspection rather than a manufacturer statement.