Want jump start want crank and sometimes it tries with a tattling noise
My car has 245000 miles.
My car has an automatic transmission.
Hey thanks for writing in about your 1990 Lexus LS400.
A no crank condition such as this will not be the alternator. You either have a bad starter or a bad connection. The most effective tool to diagnose this condition is to use a test light and follow the power from the battery post down to the starter. You will need to do this while someone is attempting to start the car.
When a bad connection occurs, power will stop at the point of the bad connection. Either this will occur or not enough current will flow to make the starter turn. If this is the case, the point of the bad connection will become hot. I suspect you have a bad connection based on your description of the tattling noise. This noise is common with bad connections. Use your hand, be careful not to get burnt, and touch the various connections after you have attempted to start the car for about thirty seconds (sometimes less). Once you find a hot connection, this will point out at least one of your problems. If you would like to have this taken care of, a qualified technician from YourMechanic can come to your location to diagnose the starting issue and perform the right repair.
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