Remove it, and take it to a GOOD shop with that warranties their work (like Best Buy

) and pay them the $55 to get it installed. That way if there's any other problems, you can always take it back to them. Make sure they bypass the AFBS if your friend didn't do so already. They might charge you more to bypass this. I understand it can be done w/o cutting wires if you use the Daewoo harness 'DO1B'.
An hour of diagnostic/repair work at a good 12v shop will cost you around $75. You might only need 1/2 hour of work to fix it, but you don't know. I'd pay the $55 and just get it done.