Hey guys i just got myself an 1984 240 so i'm not to familiar with the car yet, its only been about 2 weeks.
Today on my way to work to my surprise almost every single warning light on the dash lit up. The battery light, not the oil light, the trasnmission fluid light, the brake light, and the e-brake light (which was really weird cause i didn't have my e-brake on). The thing is the car still runs fine and will start-up no problem. The battery light is a full brightness but the other three on the right side are very dim. I was wondering if anyone could help me, im thinking a short somewhere or possibly an ignition problem. Thanks.

 

Could be a bad Alternator or wiring harness to the Alt.

 

I've had this happen, too. But I was not as lucky... My battery died soon after (driving up Mt. Baker in WA, about 3/4 up!) Anyway, I had to replace the voltage regulator. I don't know if yours is the same (I have a '90 240) but it is a little piece that is bolted to/in the alternator. Hope this helps!