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Ignition/Tuner/ECM/Fuel InjectionNeed advice on ignition issues? Questions about a tuner? Have questions about a EFI calibration or Fuel Injection? Tips on Engine Diagnostics, how to get codes, and what they mean. Find your answers here.
New to the forum and fuel injected Harleys in general. I've been reading and searching this forum for days, and I feel like I'm getting more confused as I go. Simple question, can I replace an ECM myself without dealer involvement? I picked up a 2014 Softail Slim that is in pretty good shape for a good price because this guy managed to dislodge the ECM caddy and it fell down against the rear tire and ate up the ECM. He needed money and wanted out, I wanted a deal. Now I have a bike that I just want to prove runs before I start throwing more money than necessary at it. At first I assumed I needed to go the Thundermax route and completely replace the ECM, but I believe I saw a section in a service manual about replacing the ECM and the procedure to do it. So can I get a used ECM and a service manual and make this work? DTC for the ECM says No Rsp
Also, from what I can tell from the wiring diagram, the twisted pair of red and black wires in the pic that got torn off went to the security antenna. Bike does not have security and there's no DTC related to it. Should I bother replacing?
No you would need to get a new or used ECM and then go to a HD dealership and have the ECM programmed for your bike. The new ones you can buy at any dealership come with no programming in them from HD so they can be programmed to fit many different applications.
Thank you. So that being said, is the Thundermax an acceptable option? Looks like fuelmoto has them for 699 right now, but I'll have to deal with the 18mm o2 sensor problem. I did the Holley EFI on my Nova last summer, so I feel like I can handle the software side if this is a viable option.
Also, is that security antenna needed at all if there is no security?
Last edited by od1nixer; Jun 3, 2020 at 08:43 PM.
Reason: another question
https://store.thunder-max.com/collec...l%C2%AE-models
I don't know what size bung these come with but they work great and worth the wide band and programming. As for the security you will need the antenna module to be able to use the fob and I believe from 2014 up it is needed to be able to start the bike unless you want to use the bypass pin every time you start it.
I have no idea how much it would cost to get a new or used ECM and have it programmed by a dealer. But why not get the Tmax, it's a great tuner and if you'll be doing any performance upgrades, and maybe the bike already has some. Then you'd be all set to get it tuned properly, stock or not.
Yeah that's kind of the way I'm leaning. The only reason I'm considering a stock ecm is because it might be the quickest and easiest (probably cheapest) way to verify there is nothing wrong with the motor.
My fear of going down the Thundermax/tuner route is if I encounter issues getting it to run, I'll never know for sure if it is an ECM/tuner issue or a motor/internal issue. I like to isolate as many variables as possible at a time.
For clarification, I have never heard the bike run. It came from an unknown Craigslist source for cheap. I can't believe anything dude said. Motor appears to be completely stock. Stock pipes/air cleaner all that. 4k miles on the odometer. I tend to believe that it will run, but alot of stupid things can be done to a motorcycle in 4k miles.
It's a good idea to be cautious. Before trying to start it, you can make sure you have compression, and check to make sure the pistons, pushrods and all valvetrain parts are moving. Use a borescope to look at the cylinders. You can also check to see if it threw any codes.
If you replace the ECM remember the speedometer is married to it...so unless you can find a used one with matching speedo...it will need replacing also...