Car keeps dying after new battery and alternator replacement

Hello, Dave here, contributing to RepairPal and providing expert advice since 2010. I know you say the battery and alternator have been replaced - but they need rechecked. It's possible even "new" components can be faulty. There is no reason that turning lights on should cause a stall! Check the battery to ensure it is fully charged and able to accept and sustain a load on it. Then, once you verify a known good battery installed -- the charging system must be checked for peak voltage output -- running the engine at about 2,000 RPM to do this -- and also peak amperage output. I think you'll find that there might not be enough output here (over 12.5 volts and over 90 amps output is what you can expect). You can also get some help at a shop near you! https://repairpal.com/auto-repair-near-me Click the link or call us at 877-913-1554. We'll gladly find you a certified RepairPal shop in your area.