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Q: Car stalls, P0685 code

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In the last several days, I've been having issues with my car occasionally stalling. The car can be restarted immediately and run well after that. I had the codes read and the P0685 came on. What could be the problem with my car?

Hello. Most of the time this is caused by one of two things on your vehicle. It is either because the powertrain control module, or engine computer, is failing internally, or the main relay that supplies power to it is going bad. Most of the time the relay is the issue. I usually start by testing the relay, though if it is an intermittent issue it may test fine. If that and the computer test fine I usually still replace the relay first. If you plan on having this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your stalling issue and let you know what repairs to proceed with.

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