Parasitic power drain fuse #16

Tiny
DAYWYZ
  • MEMBER
  • 2007 HONDA CIVIC
  • 1.8L
  • TURBO
  • 2WD
  • AUTOMATIC
  • 280,000 MILES
Car is honda civic 8th gen FK2 europe version. Battery died over few days, found out that it had big parasitic power drain.
Started to pull off fuses and it was fuse #16, 15A, under a bonnet, about 0.40A. In manual its says its "back up" fuse. When fuse is out, central lock system and radio doesnt work.
When I tried to pull fuses from inside under the steering wheel, while fuse #16 was in, to maybe narrow it down, but nothing changed.
Disconnected each actuator, one by one, thought one was gone bad, found nothing.
Tried different key, thought it was sending constant signal to car, but it was not it.
Found out, that these civics have problem with bluetooth modules that can drain power, but my civic doesnt have bluetooth, navigation or hands-free system.
Dont know where to look next and no more information on internet.
Monday, August 25th, 2025 AT 1:51 AM

9 Replies

Tiny
AL514
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Hello, battery draws can be very difficult on more modern vehicles with the endless amount of modules present now. Looking over our service info here in the US, its showing Fuse 16 in the engine compartment (under the bonnet) is not used of course, so maybe we can go about this a different way. When you do your testing are you fully putting the vehicle to sleep, (ie, latching all the doors when open, the hood latch, trunk latch, any place where you need to access fuse panels), and then locking all the doors and giving the vehicle a good amount of time to power down the communications networks? Thats going to be the first step, since some vehicles can take quite a while to go to sleep.
And without pulling any fuses, I would try the voltage drop method of checking for any current flow across fuses. Not sure if you are familiar with this method or not, if not just let us know, and it can be explained further. Also do you have access to an oscilloscope to actually watch the networks power down?
There have been some really crazy case studies where a module might be trigger to wake up only after a certain period of time, then might go back to sleep, just to be woken up again by something on the network (data bus) triggering a wake up signal. 400ma is too much of a draw for sure, with that much current flow you should be able to find a fuse on the interior panels with some voltage drop on it. It wont be much, but each fuse should be 0.0mv. The only Back-Up fuse I see in our service info is for the reverse lamps and that is probably not the type of back up fuse we're thinking here.
So make sure you have the vehicle fully asleep and all doors latched/locked. Give the vehicle an hour and see if you read any voltage drop on fuses in the interior panels. I would even go so far as to check switches/latches with a scan tool, checking the body control module or ECM to see if any are reporting to be On or Open, even when they are closed. Latches fail just like everything else. Any codes setting after a couple key cycles? Dont write anything off just because it may not seem to be related and if possible see if any repairs have been done recently where aftermarket parts may have been installed. The parts we are seeing now is really getting to be a problem, with many fake parts being sold on amazon or elsewhere. Check these things if you havent already and let us know what you find or have found.

https://www.2carpros.com/articles/car-battery-dead-overnight
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Monday, August 25th, 2025 AT 8:18 AM
Tiny
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After reading about aftermarket parts you wrote, I remembered that car has rear park sensors that look like they are not original. I found main module and disconnected it, and bingo, power drain dropped to normal. Funny thing is, I tried to dissasamble that module to see its name, so I can buy new one, but didnt found it, so I just connected it again, and theres no more power drain. Interesting. I think its good idea to replace park sensor module anyways, but dont know if its enough to change only module and not whole system with park sensors. Maybe you recognize it?
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Monday, August 25th, 2025 AT 12:39 PM
Tiny
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I can look the vehicle up by the vin number to see what modules its supposed to have. But yeah that's not an oem. There isnt any numbers or names on it anywhere?
That is if that vin number even comes up here, but Ill try.
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Monday, August 25th, 2025 AT 1:09 PM
Tiny
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Is there another display besides the L-R graph looking display (pic 2)?
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Monday, August 25th, 2025 AT 1:16 PM
Tiny
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Well that wasnt too hard to find, and yup its an Amazon special.
If youre going to go with this module again, I would put it on its own fuse so if there is another draw issue you can go right to that fuse to check it.
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Monday, August 25th, 2025 AT 1:19 PM
Tiny
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Yeah, just this one display in pic 2. No numbers or letters on module, nothing. Alright, I mean it looks easy to replace, just connect wires to new module and thats it? Or maybe its the sensors in bumper that is faulty? Best option should be to replace whole park sensor system somehow. It could be possible with module and sensors, but display is so far in front, under all that plastic. Is it possible to put parking system on new fuse on my own, any tutorial on how?
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Monday, August 25th, 2025 AT 8:24 PM
Tiny
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This kit it comes with has all new sensors and it looks like the same plugs on the module, just need to make sure its the same model. Looks pretty close. So you wouldnt have to run new wires for the display. Does the current one not work at all? Its not a high tech device or anything, it just uses proximity sensors to detect a close object and transmits that data onto the display to tell you if something is close on the right or left, actually pretty simple. $30 and you get the whole kit, but these are the cheap kits that may not last as long as you would like. As for running it to its own fuse, that would be a little difficult from my end since I cant locate a correct wiring diagram for this car. Like I mentioned I can look up the vin number but it may not bring up the correct power distribution diagrams.
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Tuesday, August 26th, 2025 AT 12:29 AM
Tiny
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I mean its working fine, maybe just a display is not showing digits correctly, want to change that too, but that wire from display is going all the way from front to back, dont want to break any more plastic taking it out lol. Anyway, I'll order that sensor, looks pretty much identical.
And about separate fuse, I'll let it stay as it is for now, in future I will know what to do.
Thank you very much for helping.
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Tuesday, August 26th, 2025 AT 1:14 AM
Tiny
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No problem, glad that was an easy draw to find, those can become exhausting sometimes.
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Tuesday, August 26th, 2025 AT 1:15 PM

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