My mother has a 2000 Lexus RX300 with only about 33,000 miles on it. Recently, when she tried to start the car, she says that there was a grinding sound, smoke starting coming up from under the hood, and all electrical systems failed. This was diagnosed as a “starter short”, and was repaired (battery and starter replaced, at least) for $1100. My questions are: what is a starter short, what causes it, and how can it be prevented.
It’s always possible that a starter could have or develop a short, but it would be a very, very rare and unusual thing to happen.
Without knowing all of the details I could suggest something that may have happened.
The starter drive could have caused the starter gear to remain engaged while the engine was running. This could have caused the starter motor to spin at an astronomical rate when it should not even be in operation, thereby overheating and causing a short very quickly.
A starter overrunning clutch is supposed to prevent this, but many starters do not have an OR clutch and there is no guarantee even on the ones that do.
Another possibility could be if the ignition switch or a starter relay was faulty and power was still being provided to the starter solenoid when the key was released back into the RUN position. This would cause the same effect as the first thing I mentioned.
It also could have been an oddball short that just materialized out of nowhere. If this is the case then I would not worry too much about it since it’s pretty much a freak accident type of thing.