05 MFD display and headlight not working

[dktraw]

ok guys i did some reading in the stickies but lookin for maybe some quick input though. friend is looking at buying an 05 900, and the MFD and headlight are not working, says it doesnt want to idle well either, but that the reverse does work. still has great power and runs well other than the idle. he says he unplugged a green four prong chip? but i have no idea what that is. wouldnt run at all until he unplugged that. anybody know what plug that would be? would you still have full power if the ecu was the problem with the MFD and light? hoping it would just be the relay.
i know, hard to say without doing some testing, just lookin for a little input.
thanks guys

 

[dktraw]

still been reading, and think what we are going to do for a quick test is take one of the relays of my 06s and plug it in to the 05 there before we buy it and just see if that fixes the problem. is there anyway that i could hurt my relay doing this? this way we will narrow it down to ecu, tps setting, or tps harness

 

[bwylde]

i just had that happen on my 900 and it turned out to be one of the plugs uder the frt right exhaust , and that is exactly the symptoms. No display, no H/lites, and rough idle..