Hey there. I have a 2017 Ford Fusion with an H series GWM, and I’m the process of retrofitting an AutoHold feature from Lincolns of those years.
I was able to enable AutoHold by sending CAN signals through different buses with an arduino, but that’s the most elegant of solutions So my plan is to use Sync3’s (which I upgraded to MY18.5) centerstack settings to toggle AutoHold on and off. By default it’s greyed out but I was able to fix that by mimicing a newer GWM which understands how to translate AutoHold-related messages between HS3 and HS2. In short, I’m sending the AutoHold “status” with an Arduino through HS3 and am monitoring the AutoHold switch press, then relaying that press to ABS.
Again, an Arduino definitely works, but I want something better: a GWM which natively understands how to translate those newer MY18/MY19 messages between Sync3 and ABS.
My question is: it is (relatively) safe to force flash newer GWM firmware (from a J or a K series) into my H series module (given I have a proper adapter and Forscan)? If things go south, would I be able to restore the module? Also, can someone share the firmware for J and K series GWMs?
The alternative is to replace the GWM altogether, but if I need to do that, I might as well just try to flash mine. If it bricks, than oh well, I needed a new module anyway
I understand that the newer firmware might not work well with the rest of the modules in my car, but it’s worth a try.
Physically changing the GWM is not necessary, just perform a firmware upgrade to the version you need. Make sure you have all of the files for the new version and old version in case something goes not as planned.
As far as the AUTOHOLD button, you will actually need an FCIM with the physical button to use this in the long term, rather than using a software emulator. This requires changing out the present FCIM with the newer model. You will also need to make sure the ABS firmware is correct to support the feature.
I’ve attempted the upgrade and here’s how it went:
My GWM is H series and I tried uploading J firmware. That was successful and did “unlock” the AutoHold switch in Sync3, but it wasn’t functional. It was clickable but it wouldn’t actually do anything or reflect the current on/off state of AutoHold. I debugged it and it turns out that new CAN messages were being sent, but the actual bits responsible for AutoHold were always 0, even when AutoHold was enabled.
So I then attempted uploading a K series firmware and it failed immediately on first block erase. I don’t know the exact reasons, but it seems like it’s caused by calibration size - it’s twice as large as H/J. I’m suspecting a K series GWM hardware is different from H/J.
I’m considering buying a K series GWM but from what I’ve read it’s likely to cause DTCs or broken things due to changed CAN routes, is this correct?
Also on the FCIM, I’ve tried that. Unfortunately Fusions never had AutoHold, so there’s no FCIM in existence that would have that feature. I’ve studied which pins are used for AutoHold switch on newer Ford models FCIMs (a newer Explorer and Kuga if I recall correctly) and disassembled my FCIM to see if those pins were even functional.
Turns out they were not connected to anything (just grounded), so an OEM-like physical button is not possible. That’s why I went with a software emulator. Just to clear it up, I’m not completely emulating the feature (e.g. I’m not “holding” the brake through CAN) - I’m just forwarding the AutoHold switch click from Sync3 to the ABS, which then handles it on it’s own, as if a button was pressed on an FCIM. More precisely, I’m emulating a click exactly as if it came from an FCIM.
Should I buy a K series GWM or it’s not even worth trying and guaranteed to cause problems? It’s $30 where I live, so not a huge loss if it doesn’t work.
You are correct. But it is more due to the changes in other modules rather than just the GWM itself. The K series GWM also introduced HS4 into the networking, which would not really affect your vehicle since it does not use this network.
It’s up to you if you want to experiment with it, but the odds are it will have issue with compatibility.
I can attest to what F150Chief said. I have tried using newer GWM’s in older CGEA 1.3 networks and it caused a lot of communication issues. After a lot of trouble shooting I came up with exactly what he said in that the other modules were the problem with communications. If you do it and find away to upgrade all the modules calibrations successfully so they work with a K or L series GWM that would be pretty cool.
Hm, I don’t know why I’ve never considered upgrading all other modules firmware, as opposed to replacing the hardware And that would even theoretically allow me to retrofit a K/L TCU, given I upgrade all of the modules and wire HS4?..
But man I’m pretty certain there’ll be problems with updating BCM/PCM firmware. I can try though Have you attempted updating all modules?
I have not upgraded the modules needed. When I added an L series GWM to make the HS4 network active in my Expedition that is what I came across. The L series TCU on the HS4 network worked fine and I got all the options active. So it came down to replacing the modules or upgrading the Calibrations. I know getting all new modules was gonna be $$$ and upgrading calibrations might not be an option do to different internal hardware. All of these are unknows till someone spends the time and money to find out if it works. I checked all the plugs in my case, and they were all the same so wiring was not an issue.
Got it. I’ll attempt to upgrade modules one by one and see how it goes. I’ve looked up all of the modules I could remember and so far none of them have ever had a “K” series on Fusions (at least for their “hardware” number), except for the GWM, TCU and APIM. Even BCM and TCU both were at most H or J series. Looks promising.
So I’ve made some progress. So far, I’ve successfully upgraded the following modules to firmware found in a 2019 Fusion: PCM, PAM, BECMB, GSM, TRCM, IPMA, SCME, RTM, DSM, HSWM. Most of the firmware is H series, but some (like PCM) is a K. Airbag related modules I’ll not be upgrading, and ABS/IPC I have from a newer car, so those are already K calibrations. Also, software for a couple of modules is not available on Motorcraft website, so I skipped those.
GWM and TCU I’ll be replacing, they (reasonably) have different hardware. PDM/DDM, VDM, ACM, FCIM and BodyCM might need to be replaced as all of them have different (K series) hardware, at times with completely different structure of firmware. I’ll try flashing ACM and BodyCM; if those still work after forcing K firmware into them, I’ll replace the GWM to see what issues are left.