Headunit draining battery when car is off....

[Zacmc212 10+ year member]

My car has seen very little action in the last nine months because i have been away at college.

When i came back my batt was dead, i jumped it and it died again, i relized that the radio is drawing from the battery even when the car is off... //content.invisioncic.com/y282845/emoticons/crying.gif.ec0ebefe590df0251476573bc49e46d8.gif

I pulled the fuse under the hood for the radio as a temporary fix, but i was wondering where you guys would suggest i start looking to identify the problem.

Thanks a lot.

Click to read more...

 

[btlking 10+ year member]

it will take power thats how it holds presets but some cars kill that power after so many hours or days of not running

 

[blackbonnie 5,000+ posts]

i would throw your battery on the charger. give it a full charge and you shouldnt have any problems at all with it, as long as you dont go away for a long time again.

 

[Zacmc212 10+ year member]

Ive got a brand new battery in there now, the other one wouldnt hold a charge it was pretty old and i had killed it quite a few times...

The radio still seems to be drawing from the batt even when the car is off, i put a meter up to it and it was drawing quite a bit.

 

[blackbonnie 5,000+ posts]

did you hook up your headunit correctly?

 

[Zacmc212 10+ year member]

Yea it was working fine before i left... I cant seem to figure out why it is drawing now, the only difference is i dont have my amp/subs in the car anymore. I have a hooked up set of RCAs and a caped of remote wire sitting in the trunk still...

 

[Zacmc212 10+ year member]

Any other ideas?

 

[blackbonnie 5,000+ posts]

do you have your power wire for your amp still hooked up?

 

[Omarvelous 10+ year member]

Check your remote turn on lead on your amp....if you have one...

Can you power the HU when car is off???

 

[Zacmc212 10+ year member]

do you have your power wire for your amp still hooked up?

Nope the powerwire is out

And i havent tried it yet, but im pretty sure the radio is draining the power but not actually turning on and functioning, ill go put the fuse back in just to make sure, but from what i remember thats how it was.

I know these posts are frustrating because its hard to tell without actually seeing the car, thank you for all your help tho...

 

[bikinpunk 10+ year member]

Are you SURE it's the headunit? It could very well be the amps.

Remove power wire from all amps. Check then.

It's possible the power wire is grounding or something along those lines, causing the amps not to turn off.

I've had this happen before. I simply repositioned the wire on the amp, tightened it back down again and no problems.

 

[Zakerid 10+ year member]

OK, You may have a short somewhere.

This is old school but it works...

Disconnect the postive cable, place a test light b/t the + batt terminal and the + cable, disconnect 1 fuse at a time until the light goes out (reconnect fuse if it is OK), now you know which circuit is the culprit. You will now have to check what is on that circuit for a short.

Last time I had to use this method, a customer with a Taraus was trying to make my boss pay for a battery b/c the dealership said he had a botched install. I went through this process and found that the fan relay was shorted. Replace the relay and had a customer for life... except I am no longer in the business.

 

[Zacmc212 10+ year member]

Are you SURE it's the headunit? It could very well be the amps.
Remove power wire from all amps. Check then.

It's possible the power wire is grounding or something along those lines, causing the amps not to turn off.

I've had this happen before. I simply repositioned the wire on the amp, tightened it back down again and no problems.

I dont have any amps in there anymore.... no power wire or anything left in the trunk (where my battery is)

Ill try the other suggestions tomarrow, thank you!

 

[Zacmc212 10+ year member]

Still cant figure this one out....

Is there a chance the headunit just went bad?

 

[Blove1991 10+ year member]

Unhook headunit and try another HU and if it does the same thing then I couldnt tell you