Brake, radiator, battery and oil lights stay on for about 5 minutes

[Ganeden]

Hi. I bought an old '92 lexus LS400 for practically nothing, and liked it so much after using it for 2 years that I just bought another, also for the Blue Book value.  I don't think there's another $1400 car that can touch an LS400, so now we own 2 1992 models.  But a couple of days into ownership, the brake, battery,radiator and oil lights stay on for about 5 minutes into a drive after a few hours of not driving it.  The car starts smoothly with plenty of power to the starter. I'm not too worried, since the lights eventually turn off. However, I do want to know what is going on, and the issues involved. I bought the car for my wife,and she's less interested in the whats and whys, just wants a reliable car. Any ideas? I think the battery is ok, and the alternator seems to work, and I don't think it has anything to do with the wiring in back, which I already looked at when the previous owner's jumpers shorted out and blew a fuse, before I bought the damned thing. Any help appreciated, or if the verdict is not to worry about it, I'll tell my wife

[Exhaustgases]

Alternator is suspect / voltage regulator. Also make sure the battery connections are good. And remember where the cables connect to the clamps can get corroded as well.

Verify the alternator is putting out the correct voltage. I had a similar problem it was the battery connections. Also make sure battery is in good shape.