Morning fellas (and ladies). I recently purchased an Acura TL 2007 model. It is not the type-s but o well, i love it anyways. I have heard great things about these cars and i am normally pretty handy and finding and fixing problems until now!

I come out to a dead battery one morning and think ok alternator is bad or something because the battery is new. I replace the battery anyway and start checking. Nothing is left on, tests show charging system is fine so my next thing is parasitic draw.

I get a multimeter ready, unhook the negative terminal and wait an hour to make sure the car is in "sleep mode". I touch the + lead from multimeter (mm) to the negative disconnected battery lead, and the negative mm lead to the negative battery terminal. I read 0 milliamps, i change it to voltage scale and it's reading 12.48v being drawn. I moved the leads to the appropriate side of the mm to read milliamps, i've pulled every singe fuse (not relays) and nothing changes that reading. I did open the door and read it again thinking it should change a bit with the dome light on but it did not...still 12.48v.

The car is bone stock, no aftermarket anything, so where do i go from here? What on earth could draw 12+ volts while sitting? Have i overlooked something obvious in my testing method?

 

check your bluetooth module. They are notorious for going bad and killing the battery.

The HFL (Hands Free Link) bluetooth module is in the overhead console that has the front map lights and the Homelink system. You can pull it down pretty easily then unplug the module and check your battery again to see if it's till drawing power.

I had to replace mine last year because it was doing the same thing you are describing.

 

Just tried that, no luck at all....i'm at a loss

 

I might be wrong but testing like that aren't you just getting a reading of the battery voltage? Same as if both cables were connected and you touched the leads to it?

 

You have to test for milliamps no reason to test for voltage. Just make sure you connect tester in series. If it reads zero it is possible that by living your battery unhooked for long period might have reset the parasite.

 

I thought the same thing, it mirrors the battery voltage when i test it but it would not pick up any milliamps when testing on that scale. That is what caused me to test on the voltage scale just to see if the draw was more than what the milliamp scale could read.

 

You could be right, first time troubleshooting this and I was going off of what I found online.

 

You need to test your test equipment first. Set it to amps not milliamps, leave your door opened to make sure you have some draw.

 

I would check it again. Extremely common for these to fail at your car's age and kill the battery. Might be intermittent, so disconnect and watch for a few days. Another way to tell is to feel the compartment cover after the car has been off for a while. If a drain, it will be warm.

 

I just replaced my battery (it was old anyways) as my HFL unit just died.
Not sure if its worth the $200 to buy a new one.

Hope the draw is gone - it was drawing anywhere from .85-1.2A while the car was off

 

Make sure you unplug or remove it. Even though it is 'dead' it can still draw current. There's also cheap fixes for these if you search. I personally didn't want to chance it failing again so I just go without.

 

Happening to mine as well! Same exact thing

 

I would remove the fuse from a suspected bad circuit, and test it with an ammeter. If you see current then you found the circuit where there is a problem. Then you just need to discover every component that is supported by that circuit so you can narrow down the problem or the bad component.

The hard part is making sure all the power is OFF and all the lights are off when you check the fuses for current. These TLs have all this auto on and auto off stuff.

lastly, I think all the fuses underdash are powered by a larger fuse underhood. So, if you want to start under the hood, that might be a faster way to drill down to the bad circuit.. but you need a Helms book to see all that. And I have an 07/08 Helm book for sale for $60. that is half the new price. VGC

 

only correct way to do it!

 

Another way to check your HFL is on a cold day (it's August but days will be getting cool soon) leave the car for a few hours and then put your hand on the HFL area by the sunroof. If it's warm, then it's drawing current.

 

If you check your owners manual, I think it will tell you to not leave your Auto Lights in Auto mode if you plan on letting your car sit for an extended period of time. I assume there could be an added draw on the battery (even though small) when in auto mode.

 

OP, Did you ever resolve the issue? You should start pulling fuses to figure out where the draw of power is coming from.

 

I re-read you question. And I think you have no idea the difference between current and voltage. but anyway, do you even have any schematics of the systems? If not, I have a Helm manual I will sell you for $50. Regularly $120 from Helm. If interested, send a PM to me. unsubscribing.