I have a 1990 Mustang GT and I recently took it in to have the heater core replaced (worst labor rip off ever, 9 hours) and when I got my carback, all of a sudden the turn signals and the fan/air conditioning has stopped working. At first I though, oh they just blew a fuse and iddn't replace it so I got out my fuse kit and after replacing ALL the fuses, nothing has helped. I am at a loss here and I hate to take it back to the shop because I know they will just tell me that it was nothing that they did and then try to charge me an arm and a leg to find out what it is. If anybody has ANY idea what could be causing this it would be much appreciated, it worked just fine before. Thanks.