2008 Mazda5 GT Battery Drain Issue

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2008 Mazda 5 GT
I have a problem on my 2008 Mazda 5 GT draining the battery after 2 to 3 days of being parked. I have confirmed there is an approximate continuous drain when the vehicle is off of .4-.3 Amps. I have isolated it to the radio/interior lights/keyless entry 15A circuit ("Room"under the hood). If I pull that 15A fuse the battery drain stops (verified with an ammeter). I have unplugged the radio and interior lights with no change so now I am thinking it is the keyless entry module or something else on that circuit that I do not know about.
I have tried pulling all the fuses in the interior fuse box with any change in amp draw.
I have searched this forum w/o finding a definitive answer as to what causes this or others solutions.

Does anyone know what is causing this? One has said rear defrost relay, which I pulled and no change. Another said Bluetooth module but I have not been able to locate that (my car does have bluetooth, anyone know where that module is?

Anyone know what is causing these battery drains? My guess is this started about a year ago but we did not recognize it until Covid because the car was being driven daily before Covid.
Thanks for the help!
 
Solution
Thanks for the responses, yes I have the manuals and wiring diagram and yes I have the remote start system (yes, it is a wiring PIA).
I finally found the culprit, it was the bluetooth module, which is directly behind the glove box. Once unplugged, the car went into deep sleep mode with only a few milliamps of current.

Apparently this is somewhat common as I saw a youtube video of an Acura RDX, same vintage with the same problem and solution. It is probably from the same supplier.
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2020 CX-5 AWD
Using random guesswork from the internet is not the way to approach this problem IMO. You would be much better served by obtaining the wiring diagram for your specific year and trim, and using that to systematically test everything protected by that room fuse. If you can't find a free schematic online, then consider buying a short duration subscription to one of the DIY info sites, such as Michell 1 DIY (there are other ones as well).
 
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2010 Mazda 5 Sport
I agree, you need to probably grab a schematic.

Do you have the remote start system? I yanked that out of the 2008 Mazda3 we have as it was preventing me from starting the car. What a mess of wires that taps into everything. And the dealer didn't even follow Mazda's install instructions. That thing was a recipe for a short.
 
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2008 Mazda 5 GT
Thanks for the responses, yes I have the manuals and wiring diagram and yes I have the remote start system (yes, it is a wiring PIA).
I finally found the culprit, it was the bluetooth module, which is directly behind the glove box. Once unplugged, the car went into deep sleep mode with only a few milliamps of current.

Apparently this is somewhat common as I saw a youtube video of an Acura RDX, same vintage with the same problem and solution. It is probably from the same supplier.
 
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Solution
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2010 Mazda 5 Sport
Nice! Neither of our Mazdas (2010, 2008) have that feature. So I don't have to worry about it. Thanks for getting back with the issue. This will help someone else for sure.

.5A draw though for a BT module? That's just criminal.
 
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