Recently left on the headlights of my 1991 Toyota Camry which drained the battery. One of my daughters had a portable jump start unit with her and jumped the vehicle. It started and made it home. Since then we can only start it by jumping it. Once the key is turned off, we have no power inside of the vehicle, lights, horn, chimes, seatbelt retraction, nothing. Found out the daughter connected her portable jump start unit directly to the positive and negative posts of the battery rather than using a place on the engine as the ground for her jump start connection. Where should I look for the problem, thanks.

This is just a guess on my part, but could she have first reversed the polarity and hooked the cables up backwards. This could have blown the main alternator fuse. Check that fuse. This would explain why the alternator is not recharging the battery and therefore why the battery won't start the car on it's own.

Mike

Have found the cure. I have the same issue on a 04 Camry. Thanks