battery drain

patriotu

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Hello, i ve noticed a problem on my car !!
If i dont start the car every 3,4 day the battery is drained all the way. Nothing , no power it all. I just replaced the battery and still the same problem. I ve read the internet and some other owners have the same problem but nobody gave any soultion, except using a charger all the time.
HAVE ANYBODY A SOLUTION ON THIS !
THANK YOU !!
2008 gt , manual, shaker 1000 (dont work ).
 

JeremyH

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Based on your information first guess is short in the radio pulling current.

You can find a short or source of the current draw using a multimeter that can read current. Disconnect one battery terminal and run the meter between the battery post and terminal connector, ensure the leads are in the correct socket for reading current on the meter. Reading will vary but in general a healthy system will be 1 amp or less. So lets say for example you are seeing 6-7 amps. That's a common draw for shorted lights or accessories etc. Now go to the fuse panel and pull fuses one at a time and after each check the meter. When the amp draw drops back down when pulling the fuse you have identified the circuit with the short/excess draw. Now it could be any part of that circuit or wiring but its usually the load. If it happens to be the radio you could leave the fuse out since you stated it doesn't work anyway. Sometimes light sockets get wet or bulbs deranged and simple clean of the socket and new bulb will fix a draw from lights etc.
 

07 Boss

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Probably the Shaker system. Pretty common problem, I think it is the cd changer that keeps running or something like that. I see you said it doesn't work so unhook it from it's power source and I bet your battery drain issue goes away.
 

redfirepearlgt

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F56 in the BEC is the power source for the audio head unit. It's a 20amp fuse. The subwoofer amps are on F6, F9 and F16 in the BEC as well. If an amplifier or the head unit is remaining enabled due a malfunction after the key is off this would drain the system. Be cautious when pulling these fuses as they are not a keyed power source but hot at all times.

If time is no concern, pull these three fuses (with caution), recharge the battery and then see if it starts 4 days later. If so you have isolated it to either an amp or head unit. If not, then it would be time to put the ampmeter in series with the positive post on the battery and begin pulling accessory fuses until the current draw drops. Then you will know what system (if not the obvious stereo issue) you are needing to delve into to resolve this problem.

FWIW:

The average amp hour rating (not cold cranking amps) of an automotive battery is 70Ah. In other words fully charged the battery is capable of supplying its specified voltage at a rate of 70 amps for a total of one hour before it becomes fully discharged. So, if you take the number of hours the battery is draining which is 4 days or 96 hours and divide that by 70Ah, that equates to 1.7 amps of current draw to drain your battery in that amount of time. 1.7 amps at 12vdc is 20 watts of power. Just be careful when taking this measurement. While the average "Flukemeter" would suffice being the current is likely lower than 2 amps a DC style clamp on amp measuring device would be a safer approach.

Good luck and be safe.
 
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patriotu

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I pulled out the shaker 1000 for repair and the problem is gone !!
Now, i like the look with original equipment (shaker 1000) and i really hope can be repaired. Radio works fine but cd unit is not working.
If the unit can be repaired am i still gonna have draining issues ?
I bought the car like this so i dont know how was it before...
If cant be repaired there is a good aftermarket replacement ?

THANK YOU VERY MUCH !!!
Your help saved me a lot of trouble and money !!
 

golkhl

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I just replaced the dead cd changer in my 08 Shaker 500. You can buy the oem Delco CD6 MP3 radio drive mechanism for $75 shipped from Replacementradios.com.
 

patriotu

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Whats gonna be the option if i want to replace it? Just fix it and its dead again...

Without doing any harness modifications.
 
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Wes06

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You can buy an after market head unit. And a harness that plugs into the factory one that you then wire to the stereo.
No cutting stock wires necessary
 

MassMustang

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So I've noticed that my battery loses about 0.5V of charge every 3 hours. So I pulled fuse #56 as a test and it still lost 0.5V after 3 hours. I have the Shaker 500 head unit. So before I start randomly pulling fuses, any other likely culprits?
 

redfirepearlgt

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As mentioned F6,9,16 in the BEC (not the SJB) feed the front and rear subwoofer and amps.
 

DAStangs

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AboStangster, my '05GT has started doing this. Check out the KAM or "Keep Alive Memory" built into these cars. It supplies constant voltage to the PCM or Power control Module. Also called "Keep Alive Power". Apparently this constant voltage could be the problem from what I have read. Just a suggestion but seems to make sense. Also have read that Ford dealers have a diagnostic tool to clear this but if you pull the battery ground cable for about 5 minutes, it is suppose to clear the current memory. No guarantees but hope this helps.
 

Lime1Gt

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The KAM is for the PCM module. It's required to keep all the learned driving parameters of the powertrain intact. It will normally have a very small currant draw that's not going to kill the battery for months. Clearing it is for when an engine problem has been repaired and fuel tables, etc. needs to be reset.
However disconnecting the battery for a length of time should clear PCM KAM as well as modules for other systems.
 

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