I have a Lexus LS400 from 1991. The problem is that every time i drive it somewhere and park it the battery dies. So i replaced the battery, i've done this multiple times, ive brought it to my dealer and they said there is an electrical drain from somewhere in the car. So im pretty much unable to drive this car, the only way i can make sure it doesn't die is to open up the hood when im done driving and take out CHIP #10. Then when i want to drive again i open up my hood and put chip#10 back into the engine and then it works. How can i fix this problem? its not the starter and its not the battery. many dealers have confirmed this. Please help!!

 

There could be 2 problems that could cause this. First would be a bad corroded terminal at the battery post. The second could be a bad system ground at the alternator or battery. Good luck!

 

What do you mean CHIP #10? Are you talking about the 10 amp fuse (Red) in the relay/fuse compartment?

 

yes that is the chip im talking about

 

disconnect the positive cable, get a vom and put one test lead on the positive post and the other on the and the disconnected positive terminal, if everything is off, such as the clock and doors are shut, u should see no draw, if u do u have a short, start disconnecting fuses until it drops off

 

i fixed the problem it was the alternator, my mechanic replaced it and now the car works! thanks for all your help guys!