05 V6 Hellion

Hi Everyone,
I am looking for suggestions as to what may be causing my battery drain. I am going to apologize in advance for what I know is going to be a lengthy post but I want to be detailed so as to help narrow down the problem. I have a 2005 manual V6 Mustang with a Shaker 500 audio and 53,000 miles. Love the car to death but for the past 5-6 years I have been having random dead batteries, which has been very irritating. My solution so far has been to always have a set of jumper cables handy. There seemed to be no rhyme or reason to it. Sometimes it could sit for months and start right up. Other times it would be dead after sitting for 4-5 hours. I finally broke down and replaced (what I assume to be) the original battery in August last year and still have had this problem. (This was after a cop stopped me and I found out that cops dont give jumps. Another story for another time though)

It sat over winter for 4-5 months and started right up with no problems. However since then, it has been dead every time that I go to start it (5-6 times). I figured that this was probably a good thing mainly so that I would be able to find the problem and cure it once and for all. My initial thought was that some of the diodes were sticking in the alternator causing an intermittent dead battery. I did an alternator test and found that the alternator is putting out around 14V with no load and around 12.5 or so with a load. This was done at night with the lights on at an idle and I noticed that the lights would dim some with the additional load. I have also seen the lights dim momentarily while driving at night for 2-3 seconds at a time. This is mainly what lead me to believe that it is the alternator.

At the same time, I have never had the battery light come on or any codes that pertained to the charging system. I have also seen Nuke post several times that the alternator and/or battery can pass a test and still be bad, which I strongly agree with.

I pulled it into our shop to verify that the alternator was the culprit. I hooked up a multimeter in series to the battery ground terminal and the ground cable and maxxed out the amp reading on my meter (250mA). I believe that I read on this forum somewhere that they should only be drawing somewhere between 5-20mA when not running so I figure that there is definitely a drain. I then unhooked all the wires to the alternator and made sure that the positive wire was not touching anything and measured the current again. Nothing changed! So my thought is that either this is not the culprit or I have more than one.

I started pulling fuses in the fuse box under the hood and found that my current dropped to around 2mA when I had fuses 56 (Radio), 59 (SJB#5 – Instrument Panel fuse box), 62 (SJB#7 Instrument Panel Fuse Box), 63 (SJB#6 Instrument Panel Fuse Box) & 67 (SJB#4 Instrument Panel Fuse Box).
I started reinstalling those fuses one by one to try to narrow down more and found that the current “pulses” when the Radio fuse is reinstalled. The current maxes out for initially and then hovers around 9mA for 9 seconds, then maxes out for 13 seconds. I can understand the initial current draw as the CD player always rumbles when the battery is hooked back up on other occasions. Is it normal for it to pulse? Is this because of the Shaker 500 and can it be cured by shutting the radio off before shutting the car off?

I tried to reinstall the other fuses relating to the SJB but fried my meter after testing to see if the current drops after an initial period of time (That’s what I get for replacing the fuse in the meter with some tin foil when I was in a bind another time and forgetting that I had done that. I guess that I will have to go buy another $5 multi-meter.) I was able to install one of the fuses without any difference from the pulsing current as a result of the radio, but I don’t know which one it was.

I am a little concerned about the fuses being related to the SJB. I have read several bad posts relating to that topic. I am also concerned about this because the interior of my car flooded last spring as a result of clogged cowl drains. I have fixed that problem and did it the right way by removing the entire interior to dry everything out to prevent mold and rust from occurring. I was getting dead batteries before this happened.

Has anyone ever had similar problems as the ones that I am having? Does anyone know what components I should be looking at based on the Fuses listed above relating to the SJB? I know that one of our trucks kept having dead batteries and it turned out to be a relay that was sticking. Could this be a possibility? If you need more information, I can try to provide it.

Thanks

Bitter

Someone on another forum was having problems very much like yours. It turned out to be the Shaker 500. Even with the car off, the CD player continued to cycle. His solution was to have his mechanic reset it to factory defaults. What that involves, I do not know. You can also check for error codes:

1 turn on stereo on am or fm
2 press and hold preset #3 and #6 at the same time
(the radio will go into a speaker test mode playing sound at each speaker one at a time)
3 press the #2 preset and it should say dtc codes
4 press the eject button for the cd player (this clears the dtc codes)
5 turn off radio (this saves what you did)

In the meantime, eject what CD's you have in there and be sure to turn off the unit manually whenever you park.

05 V6 Hellion

Thanks! I will try that and see if that fixes it.

Nuke

Search the forum. These S197's, especially the 05's and 06's, are notorious for dead batteries. The amps in the Shaker 500 in 05 and 06 seem to remain on if the system is left on with the ignition turned off. But it's also possible that you have a high resistance short-to-ground. The best way to tell is with an ammeter and then pulling fuses until you isolate the culprit circuit(s).

05 V6 Hellion

I performed the radio diagnostic test and didn't find any dtc codes. I have removed all of the CDs from the CD player and have been shutting the Radio off before leaving the car and haven't had a dead battery since. Does anyone know how to fix the radio on my own or is this something that I am just going to have to live with unless I want to cough up big bucks to fix it??

Thanks

Nuke

I don't believe removing the CD's is necessary. Shutting off the HU IS. And that's simply good practice on ANY vehicle.

Bitter

Assuming you like the Shaker 500, my suggestion would be to leave only one CD in at a time and always turn it off when you turn off the car. The ability to load multiple CD's is nice, but it's not overly inconvenient to eject one and replace it with another. It's the CD shuffling that seems to be the problem.

tx_zstang

Yeah make sure you TURN OFF THE RADIO BEFORE TURNING OFF THE KEY!
Also, if you do that and your battery is still not holding charge at times, get a replacement. I bought a new one that did that, sometimes randomly it would just not start, for no reason. (Avoid the 'neverstart' batteries, too!)

pcfithian

I have experienced this problem as well on our '06 GT with a Shaker 500.

I recently removed the Shaker 500 head unit, removed the CD changer from it, put a piece of black tape over the CD slot, and reinstalled it. There is no change in appearance from the driver or passenger view of the head unit.

Since we never use the CD player and use the radio or iPhone instead, it is no loss.

We have not had a dead battery since.

So if anyone on this forum wants a CD changer for a Shaker 500, PM me.

strangeshep43

It's the Radio. I have an 05 GT with the shaker 1000 and had this problem when my car was new, was told about turning Radio OFF everytime before turning car off years ago. It sounds funny but it works. Try it.