Hi Guys,

This is a head scratcher. My mechanic and his buddies can't figure out why my battery is randomly loosing charge on my 2010 Acura MDX (100K miles).

The alternator was outputting low voltage so we replaced that. The battery could not hold a charge so we replaced that. But still having issues:

1) I left my car parked at my girlfriend's for 3 days without using it - started no problem
2) Left it parked overnight at my house for 24 hours, was 100% dead when I tried to start it
3) Brought it to mechanic for the 3rd time and he can't reproduce the issue. He checked all the systems, hooked it up to test equipment overnight, etc. He even took all the doors apart and checked the automatic locks.

So right now, when parked the voltages look good and it's not drawing power.

----> The only clue I have here is when I replayed my security camera footage from #2 above, the fog lights were on when I parked my car. Only the fog lights. I don't think this is supposed to be possible..

I have aftermarket HID lights that I installed, I wonder if this is related to the issue.

Any ideas?

 

I don't know if it's also a problem for the MDX but is your bluetooth unit acting up?

 

1st thing you should do is to undo the aftermarket electrical items.

 

Makes total sense but that would mean removing my headlights!

I wonder if there is another way to troubleshoot those. They are HID lights so I wired in the ballasts, etc. I had to remove the whole bumper and it turned into a half day job!

My mechanic heard that the BT was notorious for causing issues so he said eh checked that.

 

You need to do this:


YOu have a parasitic draw somewhere..

 

You or your mechanic should unplug the Blue Tooth Module entirely to eliminate any chance it is intermittently acting up.
But the fog lights being on only by themselves probably points to the headlight mod

 

are they wired to a relay?
pull the relay out...shouldn't be too hard to access the bulb area from the fender well to throw some low beam halogen in for a bit.

 

I can check the wiring but I am not sure what you mean if they are wired to the relay. Also not sure what you mean by throwing some low beam halogen in for a bit.

I just read up on the BlueTooth a little bit. I have had the car for 6 years, are people running into this problem after a while? I guess it can't hurt to pull it if it's the easiest thing to try first.

Awesome video, my mechanic knows how to do that. The issue is that we have an intermittent problem and it the drain only happens to me, not when it's at his shop. (It's been there all week).

 

A relay pulls power direct from the battery to turn on the HID...if aftermarket HID you might have one wired in.
Halogen are normal bulbs that don't have and HID.
So basically I'm just voicing what others have...go back to bone stock and see if the problem goes away.

 

OK, I'll wait for the battery to go dead one more time (to make sure it's not a fluke, even though doubtful) and then I will go back to stock headlights.

Thanks for your help guys, I'll report back if something interesting happens.

 

Are you having any connectivity issues with the bluetooth module?
I would start there...