panel lights coming on

[Debora]

Hi, my name is Debora, from Brazil. First of all would like to congratulate this forum. It really helps a lot. I will try to make myself understanding and would ask you to reply with easy words/terms so I can understand and solve the problem I am having. Thanks!
I have a 92/93 Lumina APV - 62,000 miles 3,1 and believe it is brand new (till last week). My car is the only one in town and one of the 100 units that came to Brazil. So you can imagine how difficult it is to have it fixed here. I was driving back home (was raining a lot) with the wiper, radio and a/c on when all the panel lights came on. It lighted for 5 seconds (going back and forth). Stopped the car and turned it off (radio, wiper and a/c also). Waited 30 seconds and restarted it with no problem. It repeated twice but on different time/day. Today, leaving home it happened again and the roof light also came on. A sound (like when you forget the key on ignition) also came on.
I took it to the GM dealer, but I feel they will have a hard time to find what is going on.(the car is completely new for them). Please give me a clue.
Thanks a lot!

[LMP]

Welcome to the forum
These freak incidents are hard to analyse.
Most probably this is a ground point problem: some loads suddenly do not have their ground point to main ground and from that point the current flows in a reverse direction to other elements connected to same ground . THe lights that come on erratically are probably lit at a reduced level .
I suggest the next time it happens, stop -to be safe - and start cutting loads one after another, like turning off A/C blower, radio...and report what effect it may have on freak lights that have suddenly come on.
THis might help pinpoint the probable weak point.
SOme ground faults under front floor carpet on both sides have been reported as culprits in former reports of freak events like that.