I've got a slight problem, haven't ruled out the new battery yet. I replaced the factory battery a couple months ago with an Optima red top. The car had been getting hard to crank and a couple times I wasn't sure it was going to start.

Replaced with the Optima and it cranked over much faster than it ever had and somehow the alarm had a much longer range. Now it's been a couple months and the car is back to cranking slow again and I have to stand right next to the car for the alarm to work but it's random. It can sit overnight and crank over fast on a very cold morning and sometimes it will sit for an hour with the engine still slightly warm and barely crank over. I take a long four hour trip at least once a week so it has plenty time to charge. Checked it on the scanner and the alternator is showing 14.5 volts. Turned every electrical component on in the car and it was only using 65% of the alternator capacity at idle. I got it to 99% with the stereo turned way up but I could never listen to it at even half that level normally, just seeing how high I could get the load to go.

I've heard of the outside temp sensor draining the battery but mine never flat lines. Like I said it doesn't seem to make a difference with ambient temps, driving distance, etc, it's just a random slow cranking. Another very weird thing that may or may not be related is twice I've gone to go to work in the morning and the passenger side window is halfway down.

 

check for a short in the window circuit, maybe its going up and down all the time until the battery quits?
or your neighbor sits in the car listening to tunes at night!
Get the system load tested at any parts store- see if their test agrees with yours
What does the alternator put out at 1700 rpm , not idle

 

check the battery draw with the car off after about 20 minutes to make sure that the HFL unit is in sleep mode. I would call acura and ask them the proper draw for a TL when off. My guess is that your HFL unit is bad.

 

^^^^
Yeah, also, if you don't get about 30 feet away from the car, your cell phone will stay synced to the HFL, even though the car is not running. This happened to me because my den is only about 20 ft away from the garage. I came home and set my cell phone on the coffee table and left it there all night. My car barely turned over the next morning.

 

I replaced the stock battery with the Optima red top about 6 months ago and now if i park my car for a day or two without starting the engine something is draining the battery. It doesn't crank when i try to start it , after a couple of try then it will start but then the clock and my EDFC unit reset itself. Could it be the battery?.

 

Could be, but I doubt it. If it's not the Nav (temp flatline) TSB problem, my bet is a bad HFL unit not shutting off.

 

how do i test for this problems.

 

Thanks for all the help. I will check for voltage draw when the car is off but I'm not sure what it's supposed to be. Guess I'll be giving Acura a call tomorrow. As for the HFL unit not shutting off, I checked my phone before I started the car and the bluetooth was not connected. Is this a proper way to check the HFL?

If all else fails I might disconnect the battery after shutting it off for the night and see how it turns over the next day and see if there's a difference.

 

My car didn't start today(parked without starting the car the whole day).

 

if you want an easy way to check it, take a multimeter and hook it up to the terminals, make sure its in milliamps. It read about 22milliamps on my MDX with the car off.

 

Mine settled at 23 today, until a friend opened the door while I was doing the test. Luckily it didn't hurt the meter lol. So I guess it's not excess drain while the car is off. Voltage is over 14 with the engine running.

 

HFL unit and driver door window multiplex unit.

battery draw shouldnt be over 250mA on a mA scale.

it takes 10minutes for everything in the tl to go to "sleep"

just had one in the shop with the multiplex problem..

ive done a HFL that caused a draw.

each time you check for a draw, you have to get in the car, turn the key on, turn key off, open door, close door, and lock the doors with the remote, then disconnect the neg terminal, and run your voltmeter in series with the neg cable and post.

we were getting over 600mA draw from the driver multiplex.

with the problems youre discribing im leaning towards the above.

 

Don't feel bad, my 2008 TL is not two weeks old and has less 350 miles on it and it would not start this morning. The lights inside / dash etc. came on brightly, but when I turned the key it just rattled. It was rolled into the street to be towed to the Dealer and when we tried to get power to open the trunk, it was totally dead. Nothing was left on. The Dealer recharged it, tested it and said everything checks out fine.

First, I see comments that these cars eat batteries, but only after about 1 or 2 years. Any comments about dead batteries or electrical problems within two weeks / 350 miles?

Second, is there really no way to open the trunk unless you have battery power? There is no key hole. The Dealer says, you have to have power to open the trunk. So if you ever get stranded somewhere with food / clothing etc. in the trunk and the battery dies . . well . . . do you?

 

There is a manuel trunk release through the rear arm rest compartment. hope you just got a really bad initial battery.