Hi! I've got a great 2006 Mustang GT with an odd problem. If I don't start it every 5-7 days, the battery goes dead. I've replaced the original with a new Optima but it needs a 24-hour recharge when it goes dead. The other odd occurrence is when I try to start it, the radio comes on very loud even if it was off and turned down when previously turned off. The stereo is a stock Shaker 1000 and no other upgrades / changes have been made to it. My usually reliable Ford dealer could not find a power drain or radio problem.

Any suggestions on possible causes? Does your radio automatically come on when starting the engine? THANKS for any advice in advance!

 

(i will PROBABLY get hate for repeating myself...)
its definitely not 'unusual'
but... a lot of battery drain was caused by the cheap quality cd players...
My 2006 keeps trying to load cd's 24/7,
& causing batt. drain
had to pull the radio fuse when its parked

also get your battery & alternator tested

 

I'm sure its been said somewhere on the site more than a 1000X. All of us seem to have had the problem with batteries and the 2005+ mustang with shaker systems.

I changed head units in mine 7-8(?) months ago and have not had my trickle charger on it one time since even though it still sits weeks at a time without getting started or driven, yet now it fires right up every time.

Andretti

 

I have a 2007 Roush 427R and it has been noted that many of these cars in this era have the Battery issue. Just too much running in the background with the car is off. I have had the issues that the originator talks about in both the 2007 and 2008 head unit on my Shaker 500. Personally I had not heard of the Head unit causing the battery drain. As long as I charge my Garage queen once a week everything is fine

 

My problem was an aftermarket alarm, plus the cd player trying to load cd's, even when the engine wasn't running.