Suggestions for troubleshooting proceedures will be appreciated:

The overdrive will not engage. Is this a switch or relay problem?
I just noticed this today. I do mostly city driving and discovered this when I got on the expressway.

My AC doesn't work. The lites on the dash controlls won't even lite.
I checked the fuse, it's ok

 

IPD has a good solution for the OD problem, check their site for the instrucions... Did the AC just quit suddenly ot gradually or did it ever work? Most likey it's ouf of freon... which just escaped and is eating the ozone layer as we speak...