Tesla Model 3 Hard Start / Starts Then Dies (Cold)
The vehicle starts but then dies, especially when the engine is cold. This is unusual for an EV, as there is no traditional engine. The issue likely involves the high-voltage battery, 12V auxiliary battery, or thermal management system.
Diagnosis Details
Possible Causes
Weak or failing 12V auxiliary battery – common cause of starting and immediate shutdown in cold weather.
High-voltage battery contactor failure or BMS (Battery Management System) fault preventing sustained power.
Faulty thermal management system (coolant pump or heater) causing the car to shut down to protect the battery when cold.
Related OBD-II Codes
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What You Should Do
Check the 12V battery voltage (should be above 12.4V).
If low, charge or replace.
If the 12V battery is good, schedule a service appointment for a full diagnostic of the high-voltage system and BMS.
Related Repairs
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Disclaimer: This AI-generated diagnosis is for informational reference only. Always consult a qualified mechanic for an in-person inspection. AutOwner is not responsible for decisions made based on this information.