nynruas

My 09 MDX, every 2 weeks it drains the battery. I can jump it and it'll be good for another 2 weeks or so and then go to start it and it won't have enough juice to start. It started happening a couple months ago. I bought a new battery and it happened twice, in the first month. I took it back to the battery shop and they were going to charge it, but it was so drained that they went ahead and replaced it. Approx. 2 weeks later, same thing. I called the battery store they said I must have a constant drain somewhere. I told them they probably received a bad batch of batteries. So, to prove me right, I took the battery out of the MDX and swapped it with my '13 TL. TL also has a new battery (less than a year, no issues). So, it's been approx. 2 weeks and I'm waiting to see if the TL will drain. Well blow me over, the MDX wouldn't start this morning....

It has never stalled or threw any codes. While it 's running, I can disconnect the battery and the MDX remains on. I'm guessing this is the universal quick alternator check. If it was not charging or has a weak charge, I'm guessing once the battery starts to drain, it'll eventually stall or throw codes. MDX is driven daily. A few times, I can start it fine in the morning, drive it and in the afternoon, drained to no start. Yes, all battery connections are clean.

Anyone experience anything like this?

Thank you.

thoiboi

Time to bust out the multimeter and figure out which circuit is doing the drain. then report back so we can assist further.

nynruas

Jumped it and it’s been good, for now. Thanks for the video to reference. I’ll do this, this weekend and report back.

nick04tl

When it dies again check the Hands Free Link and the A/C Clutch Relay. Both get stuck on and draw when the car is shut off.