This just popped into my head.. I haven't given it any thought in a long time but thought I'd see what everyone here thinks. 98 Legacy 2.5 GT : Under the dash there is a couple of green connectors that plug into each other perfect. I noticed them maybe a week after I got the car.. So i was like "hmmm" and plugged them in... immediately upon starting the car .. CEL .. so i was like "What did the dealer do to my car?" (had a new short block put in... http://www.ultimatesubaru.org/forum/showthread.php?t=33887 )

So I unplugged the wires to keep the engine light off thinking "Are those supposed to be plugged in? and they unplugged them to hide a problem?" So I asked the dealer about it.. and of course they replied "Oh, those plug into a diagnostic / cpu controller computer, if you plug those into each other and drive with them plugged in, you will cause serious problems." So... What do you all think of this? My thoughts were "Why would something that's supposed to plug into a computer be able to plug into each other?" ....

um the dealer is right....they are for diagnostic....in most subarus they make the check engine light flash to indicate ecu error codes.....leave them unplugged....even if im not talking about the right ones, we all have them and they are unplugged....

Those two plugs are for diagnostics, but neither plugs into a scanner. If you keep them connected with ignition on, engine off, a number of relays and solenoids will cycle on and off. The most visible sign of it will be the cycling of radiator fans.

Wait, I got it all wrong. If you connect those two plugs, your parking lights will stay on.