Battery Drain Aftermarket Head Unit

ajswenson · March 7, 2011

Hey guys. I put a new head unit in my truck about a year ago. I guess looking back I did notice a battery drain issue, but about the same time I put the head unit in I started driving a different vehicle as my daily driver. Any way let me just get to it.

Brought the truck into the dealer thought it might be a BCM setting or something. They found that there is a significant draw to my battery like 123 milivolts or something. They said that when they removed the fuse for the radio. (#43) under the hood that this draw went back to normal (like 10). I guess my question is where do i go from here. I don't know a lot about wiring. I purchased the head unit from a member on this site and the wiring harness was already put together, I just plugged it in.

Oh if this helps the diagnosis. Occasionally my head unit will shut off while driving. The only way I can get it to turn back on is shut my truck off and turn it back on. This problem is very intermittent and goes in spurts. Like it won't happen for a couple of months and then it will happen 3 times in one week.

Thoughts?

Thanks Tony

ajswenson · March 9, 2011

Bump anyone??

TexasAl · March 9, 2011

Well, you may not want to hear this, but you might want to get the head unit checked. If it is indeed drawing excess juice on standby mode, then it may be wired incorrectly, or defective. Can you turn on the radio with the ignition turned off? If so, then that would make me think the wiring is incorrect. Any other details will help us help you.

TexasAl · March 9, 2011

#43 is an ignition on/off fuse. That is probably what your radio is wired to, so that it activated the radio to turn on when the truck is on.

ajswenson · March 11, 2011

#43 is an ignition on/off fuse. That is probably what your radio is wired to, so that it activated the radio to turn on when the truck is on.

Right, so we know that the head unit itself does not have power when the ignition is off. Where is the next place that power could be drawn. Is it possible that it is in the wiring harness itself? Can a poor connestion between the, well I don't know what to call them but "plug ins" cause this much of a draw. Sorry I didn't mention this, but when I was putting it in the harness was a little touchy, if I wiggled the connections the unit would power off. Seems like a lot of draw for that especially since when my truck is off and in the garage no one is wiggling the connectors.