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Discussion Starter · #1 ·
Hello All,
Thanks for all the great information/advice.
I typically gain enough just reading other threads but have a specific issue that, I think, warrants a new thread.
My battery (old and new one) typically dies when car is not driven for a few days. Connecting up an amp meter in series, I can see the the on-going draw is ~.25 amps (which I know is higher then it should be), but the strange thing is every ~45 seconds, the draw goes to 1.5 - 2 amps for a second or so and then comes back down to .25 amps. When the spike occurs, I can hear what sounds like the CD player trying to engage for a second or so. I disconnected the 5 connectors to the radio/CD to isolate the unit, but the background draw is still .25 amps and there is still a spike every 45 seconds, but the spike is ~.75 amps instead of higher spike when the radio/CD is connected. Not sure if this additional note is important but ~5 seconds before the spike occurs the draw goes from .25 amps down to about .17 amps, and then the larger spike occurs 5 seconds later. It's like clockwork.

I'm trying to figure out what part would spike every 45 seconds. I thought I figured it out when I heard the CD noise every 45 seconds but there is still a power spike, although smaller, even when the radio/CD is fully disconnected.

For me, it's a mystery and know the issue is quite specific but if someone has an idea, happy to hear it. I guess the next step is removing the fuses 1 by 1 but it's so painful on the back :frown2:

Thanks from Orange County, Calif
 

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I'm having a similar issue on my 2010 MDX Tech. CD Player will try to eject/load in a loop when vehicle is off and doors are locked.

Opening or unlocking the door will also trigger the CD Player to try and eject/load.

It's so strange!

Do you have any aftermarket electronics installed? Remote starters etc.?
 

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HFL unit is separated from the CD/RADIO Unit... Even if he D/C all the stereo the HFL Unit being a completely different circuit will still draw power as it supposed to activate when the Key is in Position II, When the HFL Goes bad it activates even with the key removed from the car.

The Stereo CD Loop is 100% a bad CD Driving bay failure... It has a small solenoid that will activate the CD tray movement when you open the door for some reason, That power is not the 2A draw he is seeing... 1.8-2A draw is typical of a bad HFL Unit.
 

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HFL unit is separated from the CD/RADIO Unit... Even if he D/C all the stereo the HFL Unit being a completely different circuit will still draw power as it supposed to activate when the Key is in Position II, When the HFL Goes bad it activates even with the key removed from the car.

The Stereo CD Loop is 100% a bad CD Driving bay failure... It has a small solenoid that will activate the CD tray movement when you open the door for some reason, That power is not the 2A draw he is seeing... 1.8-2A draw is typical of a bad HFL Unit.
Thanks for the background skirmich!

So the only way to repair the CD Player eject loop is to bring the unit in for service?
 

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Yep, Mine started to do that when the bastard ate my Linkin Park Hybrid Theory disc... It does that random disc tray movement from time to time when I open the door or when I start the car, Laziness has prevented me from disassembling the CD Unit to remove my disc but has never caused my battery to run flat and since I only do XM Audio I think it will keep the CD for a long time.

That high Amp Load is most likely the HFL Unit going bad.. Mine worked fine when I bought the car but since I do not use Bluetooth on my cars I just Disconnected it to be safe.
 

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OP - does the HFL still function properly?

Mine went out after 6 or 7 years. 2005 MDX. I didn't use the HFL so I didn't care, or notice that about the same time, my car wouldn't start if not driven for more than 3 or 4 days. Replacement battery died early too.
Then the alternator.

It goes like this:

HFL internally shorts, and intermittently continues to short when the car is off, either turning on, or in my case, just creating heat, but not enough to start a car fire and cause me to get a replacement car for just the cost of the deductible.

As the battery drains all the way down, or down to the point you can barely start the car, two other consequences occur.

Each time you battery is drained completely, you lose maybe 10% of its usuable life right there. Then, the alternator isn't just topping off after a regular engine start, its having to provide a full charge to the battery nearly each and every day. The stater and coils in my alternator where discolored from heat and the lacquer melted. It was fried by working too hard all the time.

Once I disconnected the HFL, no more drain, prematurely dead batteries, or fried alternators. 'Twas a $1,000 lesson over a year or two. I replaced the HFL but it was the first model which had an HFL, so it was buggy using ancient technology, and I can't port the iPhone's sound to the car, only phone calls, and only calls from numbers I pre-program into the Navi. Should have gotten Parrot or other full featured replacement that plugs straight into the back of the radio.
 

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Discussion Starter · #9 ·
Thanks to all for the great information.
I followed Skirmich's advice and checked the HFL. The unit was slightly hot to the touch even without the key connected so I was confident it was the culprit. Simply disconnected it and the power draw went from .25 amp to .05 amps and now no longer spikes every 45 seconds. Frankly, I've never used the unit in the 8 years I've had the car as it was more trouble then it was worth, at least for me.

The video link that Skirmich connected to remove the HFL was perfect. I'll leave it disconnected until I sell the car. I've seen used units on ebay for <$100 so easy/inexpensive to replace.
Thanks again! :smile2:
 
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