I've got a '04 TL that's had a dead battery several times. I've had the car back to the dealer several times but they said the battery tested OK. I was going to buy a new battery out of pocket because the battery warranty has expired.

Recently, I found out why the battery was running down. My car only has 11,000 miles so obviously it sits in the garage for long periods. That alone should not drain the battery because I try to drive the car at least once a week. The culprit was my cellphone. I've got a Razer...and I leave the bluetooth active when I'm in the house. I didn't realize that the phone was "talking" to the car...even sitting in the garage. From what I've found....the bluetooth will draw 200ma from the battery when it's "in range". Apparently, my phone is keeping the HFL active even when it's sitting on the kitchen counter getting charged..all the while draining the car battery. Once I turned off the bluetooth feature..or the phone itself..the battery stays charged. It was draining the battery down to 60% in just a few days.

 

That's odd.. I know after a minute or two the HFL in the TL will announce its transferring back to your phone to save car battery life. Odd that it continues to keep and active connection. Are you on the phone when you leave the car? I hope I don't have to disable/enable my bluetooth all the time... when I get my TL that is

 

Maybe there is a problem with my HFL, or my phone. Once....I had the HFL lockup...and the dealer was going to replace it. After they ordered the HFL....it suddenly started working again. I didn't feel like having it replaced...then having to reprogram all my phone numbers...so I told them to send the part back. Something isn't working properly...but as long as I don't have to keep the trickle charger on the battery...I really don't feel like taking the time to get a new phone...or HFL....just too much hassle.

 

That shouldn't be the case. Once your phone drops the HFL connection, it shouldn't try to talk to the car if it's off. The only time HFL would kick in is if you were to turn the car on, but not necessarily have the car cranked. Before your warranty runs out on the car, I'd advise getting your HFL replaced with the new one. There should be a TSB about that if the HFL is constantly on rather than off even after the car had been turned off.

 

Does your temperature display read ---?
There is an issue on 04s with this causing the battery to drain, search for posts on this site.

 

+1

It has nothing to do with the phone being nearby... I leave mine on all the time, and the battery in my TL does not die...

There is an issue with the software of the bluetooth on the car tho...
When your temp display reads ---, the computer is in an infinite loop. This causes your stereo to appear to lose it's presets, the temp to read ---, AND your battery will completely discharge within 2 days if left unattended...

The fix was for Acura to replace the entire navi unit. (At least at the time)... Hopefully now, they know how to simply re-program it.... This problem was on both 04 and 05 TLs.