Hey folks,

We've had this issue for about... oh... 4 years now. And, since the day she found her battery dead we've had this same problem. To make a very long story short, My wife owns an '08 Honda Accord and in early '14 she found the battery to be dead, which means the anti theft device kicked in and she couldn't get the stereo to turn on. We found her code in the glove box, and upon entering it, it didn't work. Looked her car up by both the VIN and stereo serial number online at the prescribed Honda site and found a second code, which also didn't work. However, we did find that when turning on the radio, "S/N No Code" comes up. A mystery indeed. Back then I wanted to verify the code was assigned to the proper serial so I did the 1 & 6 + Power... nothing... just the "S/N No Code." She took it to the stealership and they said they've never heard of the S/N No Code issue and, instead, swear its a cable or wiring problem (which makes NO sense to me).. but wanted $200.00.. just to troubleshoot... and more to fix it if it is indeed "broken!" No freakin' way. We even went as far as to go to a well known stereo shop, twice in 4 years, and they said they've never heard of that issue and suggested buying a new radio component to replace it (which i'm sure will have its own issues). Well, we never did anything about getting the radio repaired and, instead, she just used her phone for tunes... for 4 years. I've googled off and on for solutions to this problem in that 4 years and nothing has really panned out... meaning only a handful of people have had this issue with no resolve. Hell, google only pulls up about 1.5 pages worth of search results on the "S/N No Code" issue, and as far as I could tell, a thorough search here brought no results either (that is unless I missed it). Anyways,

Well, now we're prepping to take a 12 hour road trip in 2 weeks to see my son graduate high school and.. yeah.. we're taking her car because mine is lucky to make it out of the drive way these days, and we need a stereo. So, today, I have pulled and verified that every fuse in every fuse box were still good (they were), pulled the battery cables for up to an hour several times, tried the 2 codes which still are verified online with no success, held the power button for up to 2 minutes to hopefully bypass it like one youTube video suggested several times (to no avail), did the ! & 6 finger press show a few times both short and long presses before hitting power, and even went as far as to pull the stereo out of the dash to verify the Serial Number is correct on the stereo, which it is. Now, I can do the 1 & 6 + power, then press 2... and that will kick the radio on for the 3 minute limit, but that is all. it then turns off after 3 minutes, or when the power is disconnected and turned back to ACC it brings the code issue back, but nothing I do brings it to life concerning these supposed codes.

I'm all out of ideas here. The Honda site says the codes are good for the serial number, the serial number is correct for her car, and there are no issues with any of the electrical (despite what Honda says) that I can find. It's like the power loss erased the internal codes and now won't accept ANY input. I'm out of ideas. Anyone have any other suggestions I might try? Hell of a first post, here, but I'm desperate to find a solution at this point. Especially since she wants a new car by the end of the year and i'm getting her hand-me-down, lol.

Thanks in advance for any help you guys might be able to share with me!

 

You didn't indicate which trim level of the Accord. There are slightly different fuses protecting the circuit depending on whether the audio system is the premium or normal system.

Regardless, one common fuse that might be the cause of your problems may be due to Under-hood Fuse No. 15 (10A) - Backup Fuse. There has been another thread on this fuse before with the audio system.

Check the fuse, even if it is not blown, pull it out and re-insert it.

 

Hi! Thanks for entrusting your sanity on the trip with us! That is certainly a unique issue. Knowing the trim level (number of speakers, navi, dual zone climate) will be needed to nail down the exact model. There are "refurbished" radios available so it could be an internal failure. Replacement radios on eBay seem to sell for $200, which is pretty steep.

One popular option to get you modern connectivity and a working radio is to replace it with aftermarket (for under $200). This would be my preferred step because you can guarantee functionality and avoid the factory radio woes. You can likely do this yourself with the help of the pros at Crutchfield (and based on the detail in your post and effort to date).

https://www.crutchfield.com/S-NntD3g...da-accord.html

If you decide to go that route, this radio would be my recommendation for modern phone connectivity (but no backup camera feature), i've found Kenwood to be a good brand with good features. At checkout you'll have the option for installation accessories with or without steering wheel controls for the new radio (a $50 adder).
https://www.crutchfield.com/p_113DPX...3BT.html?avf=Y
A mech-less (no CD) model is also available for $20 less.

You've tried the things I would (short of opening up the radio to inspect the circuit board for any issues). The lack of a serial number indicates an internal failure. If the radio doesn't know it's own serial number it is not surprising it doesn't accept a valid code either.

The other things to try would be adding and removing power multiple times to maybe trick it back to life. Each time it regains power it should look for a sense of identity. I would do this at the radio fuses (ignition and memory) and not the battery terminal.

 

Thank you, folks, for your responses. I don't know how I forgot the trim level in my original post, but its an EXL with no navigation, I believe 6 speakers, and dual zone climate.

Redbull, checking the fusebox under the hood was the first thing I did, in think in part thanks to the same post your referencing. I pulled every fuse and they were all good, as well as just about every fuse in the cabin on both the driver and pax sides. If it were a fuse, however, I don't understand the coorelation to that and something in memory that shouldn't have been erased. Especially since I can get a 3 minute window of functionality where everything works perfectly. But, none the less, I checked it anyways.

keep_hope_alive, after market via crutchfield was a route I started exploring yesterday morning but I was holding out hope that there might be another suggestion I hadn't thought of before posted here before throwing money at this "project." But, it appears I may be stuck doing so. Thank you for the suggestion on which receiver to consider.... it was almost overwhelming looking at the options, and i'll continue to keep trying to trick it as you suggested until my wife decides what she wants to do. Thanks!

 

Did you ever find a solution to this? I have recently purchased a 2007 Acura RDX with the navigation package. I am getting the same no S/N message. I have tried all the tricks and like you have found no solution. I would install an aftermarket stereo but all the shops I have spoken to tell me there is no aftermarket harness for a new stereo.

 

I never did find a solution. I just bought an after market stereo and spliced the wiring together. Works perfectly.

 

Even today, your odd issue seems singular and I haven't heard of it happening to others. Aftermarket is still the recommended solution. Glad it's been a success.

 

Old post, but for what it's worth, I have the same issue. Honda Odyssey, 2011, EXL. My battery died, and on replacing it the radio is asking for a code.

The 1-6-Power gives me "S/N No Code."

I've spent so much $ recently on redoing the front end, that its hard to swallow another purchase for my beat up minivan. Will see if I can find another solution.

 

UPDATE: I FOUND THE FIX.
Honda Service Bulletin SB 10-081 (SB-10038564-8500)
Product Update: Audio Unit Software Update for Security Code, Clock Reset, HFL, and Other Listed Issues

The audio unit software needs to be updated to fix a known bug. Your local dealer should apply the fix for free (ask to be certain). Or I heard you can order the disc online (ebay?) Funny thing, is this is the SECOND Odyssey I've owned that had this problem. I guess I repressed the first memory. The first Odyssey, the software was not up to date, so I got the disc and applied the update myself. With my current Odyssey, the software was already up to date, so I needed the dealer to create a recovery disc just for my vehicle.

Hope this helps someone.