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My Civic started needing to be jumped every couple days about a week ago. Tested the battery, alteranator, and starter which are all good. So I hooked up a multimeter and found a 1.14 amp drain when my car is off. It is coming from fuse #29, which is labeled the backup fuse. I tried calling the dealership and they seemed to be less informed than I was so trying to trouble shoot it on my own. Anyone else have this problem with a successful resolution? This fuse controls the backup cam, keyless entry and start, radio, etc.
FIRST and foremost, are you allowing enough time for all of the control units in the car to go to sleep?
Could be as little as 10 minutes, or it could need up to 45 minutes without any electrical activity before all the units in the car go to sleep mode (low power stand by)
After all the units go to sleep, then you can have an accurate draw reading.
If your car is a 2014 and it still has the original battery, it could just be time to replace the battery.
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There's a whole bunch of stuff attached to that fuse. It's the memory power and battery backup power for just about everything in the car, and the power source for the data link connector.
Got a dongle attached to the data link?
The #29 fuse is shown within diagrams for:
MICU and the many things it controls, gauge control modules (tach and speedo), audio system, dome/map/trunk lights, MID/IMID, pcm, tcm, keyless, keyless access, hvac, eps, vsa, .energy management, cable reel, charging system, gauges, exterior lighting, lanewatch, wiper/washer.....maybe more.
The car was off for at least a couple of hours before running the initial test. Tested it multiple times afterwards and it is consistently at 1.15 amps.
I had the battery tested at 2 different advanced auto parts and an autozone and they all said that the battery tested good. It was someone there who suggested looking for a parasitic draw. They also tested my starter and alternator which were good.
When I pull fuse 29 overnight my car starts in the morning, if I leave it in it’s either a rough start or will need to be jumped. If I have a rough start in the morning it will die while I’m at work.
It does have Bluetooth connectivity but I have not hooked any additional equipment up to my car. There was a previous owner but it was an older gentleman, so I doubt he did anything to it either.
It’s extremely frustrating as I bought the car with 30,000 Miles on it about a year ago.
Checked the trunk light before testing amps and after I pull that fuse all my lights including the trunk still work, so the lights definitely aren’t connected to that fuse in my Civic. I don’t have any lights in the visors. I did a sweep of the car and there are no lights or noises. The only thing I noticed yesterday was that when I got in my car my phone lit up before I turned the car on. When my phone connects to my car it normally lights up. When I turned it on it didn’t light back up and was already connected. I have to double check that I didn’t just tap a button on my phone. Going to pay more attention to that today. I have an appointment for Monday but trying to figure out if there’s anything I can disconnect on my own in the meantime. I also check other threads and made sure my windows don’t still work. I jiggled the key in the door to make sure that wasn’t stuck. I cleaned under the handles of the door to make sure something wasn’t setting off my keyless entry sensor. It’s probably something out of the range of doing it myself at this point.
Just popped fuse back and checked again. It’s not connecting to my phone when it’s off. I’m completely stumped. I will post my findings after Monday since I know a lot of people are having the same problem with late model Honda’s.
I initially posted this reply in thr wtong place and have now moved it hrre.
we are having a similar problem. We also have a 2014 Civic. First owners. A couple of months ago we noticed it didn't start in the morning. We would jump it. Then it would be fine for a while. And then it wouldn't start again. But it's not always in the morning. One time it was after working somewhere for maybe 3 or 4 hours. Then it was often in the morning. It went long stretches with no issues. Yesterday it started in the morning and when I left work. Then I stopped on the way home to get gas and it wouldn't start back up. I got to a jump and it started up. Got home and parked it. About four hours later it wouldn't start again.
The battery tested fine. I don't have any extra electronics connected. We haven't narrowed down where the drain is coming from yet as I just started researching it last night.
It's really frustrating given the age and relative newness of the car. And the need to still get to work and drive around at work with this going on. When we get a solution, when we find out what's going on I'll be happy to share it here. And I'm looking forward to hearing what the solution is in your case as well. Thank you for posting about this.
You mentioned some potential issues that you checked out. Would you mind sharing them here so I can try them as well? I had read that is some older (~2009) Hondas, I did not see Civics listed, a common source of this type of battery drain is a cheap and easily replaced AC part, a fuse type of thing (sorry I am not at all a mechanic, but am learning out of necessity). That seems like an easy fix but sadly does not seem like it likely would apply here
Sorry to hear that! It’s definitely frustrating. The source of my problem is fuse # 29. The fuse box is located to the right and slightly above the battery. There’s a lid on it. Try popping the lid and pulling the fuse labeled backup over night if it stops dying that is the source. You can also buy a multimeter. You will need one that has a 10-20amp limit. They are only $25. There are a lot of YouTube videos on how to use it. You disconnect the negative charge from your battery and place the red side on the disconnected metal and black side on the negative charge from your battery. If you are getting a full amp or more it’s a parasitic draw. You should have no more than 30-50 ma’s coming out when the car is off. I took mine to several shops who told me they cannot fix it. I’m going to the dealership that’s 45 minutes away since the one here is fully booked until next week. If it’s not your backup fuse you will just need to hookup the multimeter and start pulling fuses until the draw on your battery goes back to normal. I would suggest doing this and pulling the fuse overnight or while you’re not using your car for extended periods of time as if you don’t it will eventually kill your battery and alternator from constant jumping. You can also hook the battery up to a charger overnight or disconnect it to prevent drainage if you feel it’s to complicated to locate the exact fuse. Also go straight to the dealership. It’s an electrical issue that seems to be to hard for regular shops to find and diagnose. They will either sell you a battery and/or alternator or tell you they can’t do it.
Google how to find a parasitic draw on your car battery and start watching videos. I am not a mechanic either and I have no car knowledge, it’s fairly simple and cheap to diagnose it this way. I found this video to be helpful...
Essentially what is happening is something in your car is not shutting off and causing your battery to die overnight or at work. So if you remove the fuse or just disconnect your battery until you locate the problem it will stop you from having to jumpstart your car repeatedly and extend the life of your alternator. I will let you know if I find out more tomorrow and good luck!
Ok, so my issue was just the battery. For some reason the charging system is efficient enough to make a bad battery test good in the newer cars. So regardless of what a shop is telling you, buy a battery and see if it stops happening. If it dies after replacing the battery he said it is almost always a jammed sensor for your door or hood. Start looking there. Hope this helps 😊
Ok, so my issue was just the battery. For some reason the charging system is efficient enough to make a bad battery test good in the newer cars. So regardless of what a shop is telling you, buy a battery and see if it stops happening. If it dies after replacing the battery he said it is almost always a jammed sensor for your door or hood. Start looking there. Hope this helps 😊
He did another draw and showed me what was happening. The main reason I was getting a reading was my hood clamp pulls a draw when it’s left open. There are no lights, so I didn’t bother closing it off, but for some reason when it’s open there’s a higher pull coming out of the battery. The second reason was the bad battery itself. He demonstrated that after replacing the battery and closing the hood clamp, the draw goes back to normal after a couple of minutes. I am still a little skeptical too (mostly because I know how my luck works with these things) but he seemed to be knowledgeable and told me everything he did to triple check that there wasn’t another issue going on. It took him a little over an hour to figure out it was just the battery and checked all the components before deciding to replace it and see what happened. He’s not entirely sure why the battery was testing good but since it was that was literally the last thing he tried.
He did another draw and showed me what was happening. The main reason I was getting a reading was my hood clamp pulls a draw when it’s left open. There are no lights, so I didn’t bother closing it off, but for some reason when it’s open there’s a higher pull coming out of the battery. The second reason was the bad battery itself. He demonstrated that after replacing the battery and closing the hood clamp, the draw goes back to normal after a couple of minutes. I am still a little skeptical too (mostly because I know how my luck works with these things) but he seemed to be knowledgeable and told me everything he did to triple check that there wasn’t another issue going on. It took him a little over an hour to figure out it was just the battery and checked all the components before deciding to replace it and see what happened. He’s not entirely sure why the battery was testing good but since it was that was literally the last thing he tried.
Hello, I have the exact same issue with my 2015 Honda Civic. Did installing a new battery resolve your issue? Appreciate your time in sharing these details.
Hello, I have the exact same issue with my 2015 Honda Civic. Did installing a new battery resolve your issue? Appreciate your time in sharing these details.
Yes! Replacing the battery worked. I would definitely start there and hopefully save yourself some trouble.
Yes! Replacing the battery worked. I would definitely start there and hopefully save yourself some trouble.
Thanks a lot for your quick response. It is surprising how all my battery checks always show the battery as "good". Did that happen with your previous one was well? Do you mind letting me know how long it has been since you have had no battery issues? I have been reading some other forums as well where they say the problem reoccurs in a few months even after installing a new battery. Thanks once again!
Excellent!! Sorry I just now noticed your previous response. I had no further issues with my car after that. I sold that car but I had it for a long time after this issue and never happened again. The mechanic said that the charging system in the civic (the alternator) is highly effective and you obviously will drive it somewhere to have it tested so it will come back as good and potentially take a few days to die again vs other cars that will just not start once turned off 🤷♀️. Sounds like that could be why but not positive.
My 2012 LX has just over a 1 amp draw coming from "backup" fuse 29 as well. It will drain my battery overnight. Battery has already been replaced as well. Has anyone with these symptoms actually been able to resolve their issue? Its crazy how many people online have the exact same problem. It doesn't appear to be just on 9th gen civics either. Seems other Honda owners in general are complaining about a draw coming from their "backup" fuse.
I was able to resolve my issue. On the driver side door handle the touch free door sensor was not going to sleep once the car was turned off, so it would drain the battery overnight. Unplugged the sensor inside the door and have not had a issue since.
I was able to resolve my issue. On the driver side door handle the touch free door sensor was not going to sleep once the car was turned off, so it would drain the battery overnight. Unplugged the sensor inside the door and have not had a issue since.
Hi, did that resolve your problem? I'm having the same problem with my '12 civic.
4Pointslow, did you solve your problem? I'm having the same problem, 2012 civic, no touch free sensor, and no hood clamp sensor, and i put in a new battery but that still did not help. Fuse 29 has a huge draw.....
HI, did you have some trouble with your driver door? disconet the main lock system located inside the drive door and check the amp on the fuse 29, if the value is below 1.0 amp the problem is located right there.
let me know if you do that.
regards
Door Latch, this is the name of that part.
Last edited by Mikebautista; 11-03-2021 at 01:03 PM.
Reason: add a picture
Mikeb. The 1.0 amp draw comes down to close to zero within a few seconds of the battery being hooked up. So there doesn't appear to be a problem with residual draw after all. But if I have further complications I will try your idea. Dave
I have a 2014 Civic EX with toughscreen radio. New battery (Duralast Gold top) installed May, 2020. First had the battery die when sitting while I was on a two week vacation in July 2021. If driven daily, there was no need to jump it. Then my daughter has been using it at college. She lets it sit for a week or more at a time and needs to jump it each time she gets in. Now, we have it at home again and everyday it needs a jump. Autozone tested the battery = passed with 90%. They thought maybe an alternator issue but that checked out ok wiht the multimeter. Onto the fusebox. I got a draw on #29. This is where i passed the car to a shop to go from there. They first diagnosed the draw as coming from the keyless door lock module. They disconnected the module, draw went away, reconnected, draw came back. They came back again and the draw was gone. They noted there has been issues with the bluetooth system being a source of draws but, we have the touchscreen radio system that has the bluetooth embedded there, no module. Now they are not sure what the issue is. They have the car overnight to see what happens. Maybe the keyless door module was loose and reconnecting solved it?
Has anyone had an issue withe the #29 and the touchscreen audio system related to bluetooth? Are these comments regarding replacing the battery really all this is?
My Civic sadly joins the almost-nightly battery drain, though it's an 06 Ex. 2 year old battery, very little driving (5 miles a month in the last year), yet drains almost nightly. When I used to drive more, it would last a few days.
The emission indicator recently came on (or maybe it's the check engine light - need to double check). Could that have anything to do with this?
My car knowledge is limited (oops), any suggestion on where to get an electrical test to determine the culprit? Auto Zone?
I have a 2014 Civic EX with toughscreen radio. New battery (Duralast Gold top) installed May, 2020. First had the battery die when sitting while I was on a two week vacation in July 2021. If driven daily, there was no need to jump it. Then my daughter has been using it at college. She lets it sit for a week or more at a time and needs to jump it each time she gets in. Now, we have it at home again and everyday it needs a jump. Autozone tested the battery = passed with 90%. They thought maybe an alternator issue but that checked out ok wiht the multimeter. Onto the fusebox. I got a draw on #29. This is where i passed the car to a shop to go from there. They first diagnosed the draw as coming from the keyless door lock module. They disconnected the module, draw went away, reconnected, draw came back. They came back again and the draw was gone. They noted there has been issues with the bluetooth system being a source of draws but, we have the touchscreen radio system that has the bluetooth embedded there, no module. Now they are not sure what the issue is. They have the car overnight to see what happens. Maybe the keyless door module was loose and reconnecting solved it?
Has anyone had an issue withe the #29 and the touchscreen audio system related to bluetooth? Are these comments regarding replacing the battery really all this is?
update: shop chased this draw to the sensor in the driver door handle. They disconnected this. No draw. New battery installed as well. My kid has the car for six weeks now. No reports of drains. The sunroof no longer works but, that’s a small price to pay at this point.
05-29-2018
Re: 14 Civic Ex Backup Fuse #29 parasitic draw 
