Car battery kept dying, even though the battery was fairly new and still under warranty. AAA came three times to jump start me and insisted there was no issue with either the battery or the alternator. Took it to repair shop and they said the battery needed replacing and did so, but the issue did not resolve. After several days trying to diagnose the problem, they indicated the Hands Free Link (HFL) system was faulty and draining the battery because it does not shut off properly. This part can only be purchased from the dealer for $550 plus ~ $200 in labor for my mechanic to install. I asked if they could just remove the HFL system altogether, as I never use it (it's ridiculously cumbersome and outdated and not intuitive at all... in fact, one has to read specific commands from a script in the manual in order to do anything). I haven't been able to successfully pair my phone with the system in years, but I don't know if that's related to the battery draining issue.

After learning what the issue was I looked it up. Lo and behold, this has been common problem in Acuras for many years, that they fully know about, but will not issue a recall or reimburse for replacement. In fact, they just recommend replacing with the same faulty part that will continue to cause issues. There is now a class action lawsuit in process but I'm not sure I'll ever see the $ before I get a new vehicle. Logging here just so more cases are documented.

There is a persistent problem with these generation (2009) MDX cars. This is a recurrence of a battery drain issue that occurred two years ago. The original battery drain occurred due to the failing Hands Free Link module which failed in a constantly polling condition which drains the battery, often overnight.

Solution 1: Disconnect the damn module. Result 1: Battery lasted another two years without problem.

Approximately 6 months ago, the battery drained again, while my daughter had the car 10 miles away with our grandson. I was able to immediately jump start the vehicle with a booster battery and once home recharged the battery. This charge lasted until last month later. Once again, my daughter was out with our grandson and the car wouldn't start. Similar situation of being 10 miles away prompted me to purchase a new battery the following day. Fast forward to this past Thursday and the car won't start again while out. Jumping and recharging of "new" battery purchased in June followed. Began diagnostic search and find references to Homelink remote garage opener issue, and A/C Clutch Relay stuck issue. Disassembled Homelink system and found a loose wire. Reassembled. Replaced A/C Clutch Relay part.

Solution 2: Replaced A/C Clutch relay. possibly disconnect Homelink but this also disables other items in overhead console, either the power moonroof or the lights. Result 2: Pending.

Ran full code read diagnostics with Bluedriver module. System reports "no codes" for this at all.

The MDX forums are replete with complaints about the Homelink being constantly powered "on" even when the ignition is off. Seems that this problem has been ignored by Acura.

Update from Oct 11, 2021: Two weeks after the dealer performed an electrical charging system diagnostic check which took half a day and cost $200, and found no problems, the "Check Charging System" dash information warning came on and stayed on. I verified that the alternator was not providing current to the battery.

Returned vehicle to dealer for additional diagnosis and repair. Result was a replaced alternator and another half day in the shop. Cost $2000.

I was having issues with dead batteries and replaced two batteries. After still continuing to experience issues with battery drainage, I had a mechanic run tests and found that the Blue Tooth Module /HFL Device was defective. I removed the module and drove with no issues for three months until I had the disposable income to purchase a new factory Bluetooth module /HFL Device from my Acura Dealer.

We replaced the module three weeks ago and I am now experiencing dead battery issues resulting from the Bluetooth module.

I am aware of a Class Action Lawsuit regarding this part . https://topclassactions.com/lawsuit-settlements/lawsuit-news/840256-acura-handsfreelink-defect-class-action-lawsuit-gets-trimmed/

I am at a complete loss as to how resolve this issue. The part being electrical is not returnable to the dealership. I have no choice but to again disconnect the HFL and be out the $480.00 I paid for it.

How do I sign up for the Class Action Suit. I am reaching out to Acura but from what I have read they are not taking ownership of the problem and rectifying it so I do not have high hopes for resolution from them .

I've had to jump start my 2009 Acura at least a dozen times in the past 5 years. My battery would be dead without any lights left on or anything else that could have caused the battery to die. I've also replaced the battery 4 times during these past 5 years. This last time I decided to have the car towed to the dealer, which is 16 miles away. They did give me a loaner, but 2 days passed and no word on what's wrong with the car. I call them yesterday to let them know the CD player stopped working and so did the auxiliary feature where I plug my phone into the cable to be able to hear music from my phone through the audio system as well as the remote control to open the doors. I am being charged $140.00 for a diagnostic test and this morning they call to let me know they found one of the drains on the battery to be the Bluetooth hands-free link and that there is another drain which they need to still check and will need to charge me another $140 to diagnose. I told them absolutely not going to pay an extra $140 for a diagnostic test and that I've read online that the 2009 Acura MDX has electrical issues. This morning I find a class action suit for this issue with Acura from 2005 models on and joined it. The lawsuit was filed in 2016 and is still pending. No one I've spoken to at the dealer has any notion of this class action suit, or so they tell me.

Here's the link to it, in case you've had a similar issue.

https://www.hbsslaw.com/cases/honda-acura-handsfreelink-defect