2008 Battery Drainage

[The Shape]

Ok I have an 08 v6 with the notorious shaker 500. Battery was draining over night and I read all the crap about the ty radio/amp issue. Completely unhooked the radio harness from the head unit. Seemed to stop the battery drain....for about a year. Now it's doing it again (radio still unplugged). Are the amps powered seperately? I have tested each fuse inside and out and see nothing that would drain the battery dead overnight. Unplugged the trunk bulb, etc... something is still killing the battery. Any suggestions? I'm wondering if the amps are still cutting on even with the radio unhooked. ...I don't know what else. Sick of this battery draining gremlin in this car. Oh...I've tried 2 new batteries as well.....

 

[Noobz347]

Ok I have an 08 v6 with the notorious shaker 500. Battery was draining over night and I read all the crap about the ****ty radio/amp issue. Completely unhooked the radio harness from the head unit. Seemed to stop the battery drain....for about a year. Now it's doing it again (radio still unplugged). Are the amps powered seperately? I have tested each fuse inside and out and see nothing that would drain the battery dead overnight. Unplugged the trunk bulb, etc... something is still killing the battery. Any suggestions? I'm wondering if the amps are still cutting on even with the radio unhooked. ****...I don't know what else. Sick of this battery draining gremlin in this car. Oh...I've tried 2 new batteries as well.....

First.... How old is the battery? This is important. Not so much how old you 'think' it is:


Carry the two
it was a Tuesday
Same day the dog
ate the sofa and keys


If it's not a Motorcraft or DieHard Gold+ or top-of-the-line Interstate battery and is approaching 4 years or more... It's time to go.

The batteries that I've mentioned (including OEM batteries for Chevy and some others), carry a much higher reserve capacity than what you find in your average auto-parts stores. They also generally last 2 to 3 years longer than parts store brands.

Every vehicle has a drain. My Suburban in addition to upgrades, has one of the highest I've seen (think: mobile command center lol). I get 3 years tops out of part store batteries and nearly 7 from OEM. They're not just more expensive because FORD (yes, I'm old enough to have doen this myself ).

Anyway.... Once that most important piece is squared away, then troubleshooting begins. How handy are you with light probe and multi-meter?

 

[The Shape]

9 months...max

 

[Official NOCO]

What type of weather and environment in the car stored in? If you drive your mustang infrequently, and it's stored in a cold environment then your batteries performance has been going down since it was purchased. Do you keep it hooked up to a charger/maintainer?

 

[David Young]

This is the video i used to find my slow draw from my battery on my 25 year old truck
View: https://youtu.be/KF1gijj03_0