Okay, so this is my 7th mustang but my first of this body style, I just bought a 2005 Mustang GT Manual its got a Power Akoustic radio in it (the previous owner put it) but as soon as i drove off the lot my gauges started messing up, like my RPMs werent reading at all, speedometer wasnt working, and neither was my coolant temp gauge... so i take it back to the dealer and ask them to run a diagnostic test on it, they said it could be the after market radio.. could that be true? ive never heard of that nor does it make any sense. Thanks!!

 

not related to the radio at all. sounds like it had issues prior and your now having to deal with said problems. sounds like the stepper motors in the cluster are bad and need replaced, its not a huge problem if your good with soldering and small electronics. there are places you can find that do this repair fairly cheaply though.

 

2005's thru mid 2006's have chronic gauge issues. The problem is with the stepper motors. Do a search in the forum and you'll get an avalanche of info.

 

+1, I had to replace my cluster after a failed stepper motor change. However if you are patient and have a steady hand with a solder gun it is easy to do.

 

If they didn't have the radio to blame, it would have been the way you pulled off the lot.