Handlebar speedo
Intermediate
Joined: Oct 2021
Posts: 39
Likes: 5
From: Colorado
Adi. B.
You will still need to add a graduated level sensor of some sort, and will need to remove the resistor plug and jumper the ground through that plug. This jumper is part of the kit for the level sensor for sportsters. And if you saw my post after I was asked about the 2019 model, youll see I basically said to do the same thing you did. I might try and see if my local HD dealer could reflash my ECM to the newer firmware, or if a new ECM needs to be purchased. You are right the p/n is the same, with the exception of the A on the end.
You will still need to add a graduated level sensor of some sort, and will need to remove the resistor plug and jumper the ground through that plug. This jumper is part of the kit for the level sensor for sportsters. And if you saw my post after I was asked about the 2019 model, youll see I basically said to do the same thing you did. I might try and see if my local HD dealer could reflash my ECM to the newer firmware, or if a new ECM needs to be purchased. You are right the p/n is the same, with the exception of the A on the end.
Novice
Joined: Jan 2020
Posts: 20
Likes: 2
From: Colorado
@007Duc
You are correct. I got ahead of myself (probably too excited when I found out the solution) and read your later responses after posting mine.
So basically the softail gages will only work with a fuel level sensor kit, since the factory low fuel sensor has a ground that needs to be bypassed and the low level sensor won't work if it is bypassed in stock set-up. I missed that part in my analysis. Thanks for pointing that out.
Regarding your ECM upgrade, the P/Ns for the ECM for both 2017 and 2020 Sportsters is the same (41000326A, I confirmed this on the online microfiche), so just a firmware upgrade would be ok and you won't need to get a complete new ECM (theoretically). However, you will either need to add a wire to connect the fuel level sensor to the ECM fuel level processor, or upgrade the main harness to match the that of 2019-up Sportster.
You are correct. I got ahead of myself (probably too excited when I found out the solution) and read your later responses after posting mine.
So basically the softail gages will only work with a fuel level sensor kit, since the factory low fuel sensor has a ground that needs to be bypassed and the low level sensor won't work if it is bypassed in stock set-up. I missed that part in my analysis. Thanks for pointing that out.
Regarding your ECM upgrade, the P/Ns for the ECM for both 2017 and 2020 Sportsters is the same (41000326A, I confirmed this on the online microfiche), so just a firmware upgrade would be ok and you won't need to get a complete new ECM (theoretically). However, you will either need to add a wire to connect the fuel level sensor to the ECM fuel level processor, or upgrade the main harness to match the that of 2019-up Sportster.
Intermediate
Joined: Oct 2021
Posts: 39
Likes: 5
From: Colorado
I have already tapped pin 12 in my existing ECM harness and can grab the fuel level signal from the resistor plug where you jumper the ground. There are three pins in that connector (ground / ground to sensor / level signal) In fact, I’ve even gone so far as to temp install a float style M8 level sensor. It’s how I know my current firmware won’t pick up the signal. Now if only HD will update the firmware to the more modern version? Might have to give them a new VIN?
Novice
Joined: Jan 2020
Posts: 20
Likes: 2
From: Colorado
If you have the wiring done then that's majority of the work. I hope the M8 fuel level setup works so that you don't have to go through all the work again.
Regarding the VIN requirement for ECM update. If a bike needs a new ECM, won't the dealer be able to transfer the VIN and mileage information to the new module when installing the firmware? Shouldn't it work the same way if you're trying to upgrade? You can confirm with a dealer but I think it should be possible with the same VIN.
Regarding the VIN requirement for ECM update. If a bike needs a new ECM, won't the dealer be able to transfer the VIN and mileage information to the new module when installing the firmware? Shouldn't it work the same way if you're trying to upgrade? You can confirm with a dealer but I think it should be possible with the same VIN.
Intermediate
Joined: Oct 2021
Posts: 39
Likes: 5
From: Colorado
You are correct that the dealer would transfer the VIN and mileage info in the case of an ECM replacement. My apprehension is that if I were to just update the ECM using a 2017 VIN that it will not include the firmware for the fuel level sensing that is present on the 2019 VIN file. And there would really be no way for me to verify that.
Novice
Joined: Jan 2020
Posts: 20
Likes: 2
From: Colorado
Sorry I should have been more elaborate. What I wanted to say was that can a dealer not update a 2017 sportster ECM with a 2019 firmware, and transfer the VIN and mileage (plus other information as required) while doing the 'upgrade'?
Intermediate
Joined: Oct 2021
Posts: 39
Likes: 5
From: Colorado
Not sure yet. Got to find a dealer that will let me actually talk to a tech. Not just an idiot service writer.
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Intermediate
Joined: Feb 2022
Posts: 28
Likes: 4
From: Seattle
My dealer tech team are interested in the mod, because they also like to do some things like that so they probably welling to help if I need some different things. Try to build a relationship and sell the project.