A few weeks ago, my cruise control stopped working. It will turn on but will not set.
Also a few weeks ago, my climate-control fan decided to work only when set to high.
Also a few weeks ago, my fiance changed my spark plugs for me. I don’t want to ask him if he could have messed something up, because I don’t want him to be offended (or to stop doing all my maintenance).
So did he mess something up?
It might be just coincidence.
My climate-control fan failed a few years ago. The Blower Resistor has a series of resistors for different fan speeds, and they failed one at a time. That may be your problem. If you can get at it, it is an easy part to replace. Alternatively, you might have a bad switch.
If the troubles occured right after the maintenance was performed then I would have to suspect that he may have accidently disconnected something but the things you mention aren’t near the plugs really, except the cruise control system perhaps. Check all the fuses for any blown ones under the hood and in the dash.
Other possibilities for these troubles could be a problem with the blower motor relay and the safety switch for the CC system on the brake pedal may be out of adjustment.
If you are doing your own maintenance on the vehicle then one of the best investments you can make is getting a factory service manual for it. Check out EBay for some good deals on them.
it could be the fan selector switch/cruise control switch