We have replaced the battery, alternator, starter, and module. It still won't start. We checked the fuses and they are good. When we would drive it the battery would go down but then go back up. It would be fine the next day until it was driven for 20 minutes.
My car has 151000 miles.
My car has an automatic transmission.
If the charging rate (or battery voltage) is fluctuating a lot as you drive, then the charging system should be diagnosed and, as well, the possibility of excess current draw (phantom electrical loads) should be considered, particularly if the battery is discharging. If you are in a situation where the starter motor is not even cranking the engine, among the first possibilities is a discharged battery (again, possibly due to a charging system fault), excessive voltage drop in the starter circuit due to poor electrical connections, or a dead starter/solenoid. Prior to performing diagnostics the battery should be load tested. With a battery in good condition (or, in your case, a new battery) and the immobilizer (security) system off, if the starter motor does not operate at that point, there are only two possibilities: 1) either there is no power to the starter motor/solenoid, or an excessive voltage drop, hence the entire starter circuit would have to be diagnosed; or 2) there is power but the starter/solenoid itself is bad and that includes intermittent starter operation which does happen. If you desire that a specialist from YourMechanic determine which of these is the issue, and get it resolved, please request a no start diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
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