I've been having some weird electrical problems recently. I think I figured out the AC, but my radio is still acting up. When I turn my key to ON, it doesn't come on, the only time it will come on is if the engine is running. If I turn the engine off, it shuts off immediately which before it would stay on for 10 minutes or till the door was open. On top of that it will keep turning off and on periodically. I have checked the fuses and they seem to be fine. There is no dampness around the fuse box (I have a 2009 so that was apparently taken care of then anyway), and I checked the wiring behind the radio and everything seemed good. I did just install a Roush super charger and some gauges. The only thing I did that involved something near the radio was the add-a-fuse for the gauges. I'm not really sure what to check from this point and its getting kind of frustrating. Any suggestions?

EDIT:
Does anyone have a write up for the autometer AF gauge using the add-a-fuse to make sure I did that right?

 

My first thought is an intermittent relay. I don't know if the wiring of the 09 is the same as the earlier years but you can try this, which has wiring diagrams: http://iihs.net/fsm/?dir=1

 

Do you have factory radio or aftermarket? maybe you blew a fuse by the smart junction block! were did you get the key on power for the gauges?

 

It is an aftermarket, should have said that. Pioneer AVH 3200. I checked all the fuses inside the car and under the hood, they are all fine. I pulled it last night and looked at all the connections and they seem fine as well. I didn't get a chance to check them with a volt meter. To get power for the gauges, I used the light dimmer for the boost gauge (just a mechanical gauge), and an open fuse slot that had power when the key was on. I forgot the slot number, but it is right below the 5a fuse for the AC.

 

I would double check the 10amp fuse on the back of the unit. Another thing to try, is reset the unit. There is usually a little reset button that you need to pop with a small paper clip. Should be at one of the corners of the unit on the face.

 

So I think there might be a bigger issue here. My temp gauge quits working after a few seconds of the car being turned on, and my AC blows hot, but is full of Freon and everything. This might be a little scattered so hopefully someone can keep up.

First problem was my AC, was told it was the AC control unit because it was full of Freon and the compressor would kick on if power was run to it. It is NOT the AC control unit though, because I tried it in my friends mustang and it works fine.

Second Problem radio will come on for a few seconds, turn off then keep going on and off. It also does not stay on if the car is turned off, and will only turn on when the engine is running. All connections and fuses have been checked and are fine.

Third problem the coolant temp gauge will start to climb (if I turn the car on after it is warm) then the very second the radio cuts out the first time will stop working and not work again till I turn the car off and on again. At the same time (as the radio cutting and the gauge stopping), the interior lights will flicker .

Fourth problemI have a check engine light with a "Cylinder Head Temperature Sensor Signal Greater Than Self-Test Range" or something similar, p1289 I believe. I'll double check when I get home.

So I think there must be some kind of electrical gremlin rooting around.


Fourth problemI have a check engine light with a "Cylinder Head Temperature Sensor Signal Greater Than Self-Test Range" or something similar, p1289 I believe. I'll double check when I get home.

So I think there must be some kind of electrical grimlin rooting around.

 

Or a RAT nestled in your engine bay...

 

Right now, I wouldn't be surprised lol