90 cougar dash/radio

I recently bought a 90 mercury cougar 3.8L Yesterday I replaced the stock radio and it was working fine... for about 5 minutes, all of a sudden the digital dash and radio went dead at the same time. I removed the radio and that did nothing. They are not on the same fuse. I checked ALL the fuses in the drivers side fuse box(the only one I know of) and ALL fuses were good. My Chiltons manual has engine wiring but not the wiring for the interior so no help there. If anyone has any ideas or wiring diagrams I could REALLY use the help, I have no speedometer, and cant drive until I do.

Did you get the proper wiring harness for the car or did you just cut off the plug and splice the radio wires to it. I have an EVTM for the 89 cougar but it shows no common point between the radio and the dash. I am getting ready to replace the radio in mine this weekend, just got all the stuff I need from crutchfield. I will let you know how that goes...

New radio went in fine and did not take out the dash......been in and working now for 4 days. Hopefully you can find the problem with yours. If you did not solder and heat shrink the wires, you might have had a hot wire pop loose and short to the chassis.....that would be the next thing to check

its a small 5 amp fuse in the main distribution block under the hood. same problem happened to me. quick fix just hope i can help.