Ordered a SYNC 4 APIM, lets see what happens once it arrives!

Yes the new ethernet cables with the 2 pin connectors. Been looking for that connector on Tyco’s website… definitely have leads on what it is but not exactly sure. Would love to have the real part from Ford before going out and purchasing pricey connectors that might not even work.

What year/make/model vehicle are you going to try on? I have a gateway module as well that can communicate over HS4 but I don’t believe that’s the source of the boot message for Sync 4. @F150chief sent me over the latest FORScan beta that supports Sync 4 so maybe there’s a chance I can get connected.

We shall see…

2018 F150 is the goal to get it working in. I may hook up the gateway module on the bench and tie it into the CAN bus and see what happens.

I have also read that the actual Gateway Module (the one with OBD port) may need a firmware update to 2020-ish calibration, but haven’t researched that much. I may pick up a 2018-2020 GWM for use on the bench to mess with firmware on so I’m not messing with my daily driver.

The existing GWM in the F150’s (2015 thru 2020ish) do not support ethernet (HS4?). Even updating the firmware will not fix that issue. But the older module should bring up the Sync 4 unit on the bench test.

For note: I have not seen the ethernet referred to as HS4, so uncertain about the terminology since that has always referred to CAN-BUS. Also, the GWM that does support ethernet is referred to as GWM-A in the limited wiring diagrams I have seen for the 2021 vehicles.

Honestly just go out to your truck and disconnect pins 53/54 and plug in Sync 4… then try to connect the latest FORScan release and let us know if it recognizes it :sweat_smile: It should definitely boot up, but what I’m trying to figure out is getting FORScan/UCDS to recognize Sync 4 in the vehicle.

Is the OBD2 Smart Data Link Connector (SDLC) what you’re using as your Bench tester? How’s that working out? I gave that a shot before with a 2018 Expedition SDLC but couldn’t get it to boot anything. Did you essentially provide 12v power to it via the 24 pin connector then output each CAN signal line to the 54 pin APIM connector :eyes:

if that’s the case, part of me wants to try to just say f*ck it and make a OBD2 male to 24 pin connector and throw a SDLC on my FoST and see if it sends the correct boot signal to Sync 4 :sweat_smile:

sync 4 enabling features - YouTube

2.3.44 test version…

This is probably what I’m going to try first… adding HS3 into my ol girl.

2017 Fusion Gateway Module Diagram + DLC

2017 Focus Data Link Connector (no smart DLC or GWM)

Then we’ll run some wires up to the Sync 4 system and go from there.

I’m using an STM32 to send the boot message, but I’ve got the SDLC wired in for an OBD interface. This allows me to connect to Sync 3 APIMs fine with UCDS, but no luck with Sync 4.

If what @F150chief says holds true, UCDS isn’t working because it’s probably trying to use HS4 which isn’t present in the SDLC I have. My guess would be that the same would happen in my truck because of the SDLC.

Almost seems like a 2021 GWM/SDLC is needed at least on the bench to connect, and then see if there’s ASBuilt that can be changed to support the older architecture. There are a couple of references to architectures in the AsBuilt properties I have reviewed using UCDS.

I’ve was under the impression HS4 and Ethernet are separate, but haven’t looked at the wiring diagrams in a couple of weeks. I’ll do some more research this weekend when I’m back to my laptop.

The GWM-A that I have has the newer Ethernet ports, as well as a standard wiring connector with CAN bus, power, etc. This is kind of what I was wondering “out loud”, is if wiring the GWM-A into the mix will allow things to function normally. As far as I have read, the Ethernet connections are mostly for software updates and diagnostics, so in theory that’s probably not needed just to get an APIM working.

This is what I was trying to get at… essentially what I want to know if I am able to actually get Sync 4 to connect to my bench tester to a point where I can edit AsBuilt, are there asbuilt settings in there that when set properly, will allow Sync 4 to understand boot messages sent from C1MCA architecture… because if that’s the case then Sync 4 becomes a plug and play swap for most cars 2011+ as long as a bench tester is able to program it to know to look for the legacy boot message.

One of us just needs to find a 2021 SDLC module :grin:

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This is not the case, review the video above. All he did was disconnect the HS-CAN pins 53, 54 in the existing APIM connector (HS1-CAN), which in Sync 4 is not implemented. Also, from the FFClub thread referenced at the top of this thread: Ford moves to CAN FD, UCDS will be relevant. UCDS already supports SYNC4 (configuration)… I do not use UCDS so I can’t tell you how they did it, but I suspect the latest version should just work, not unlike FORScan.

An older GWM should work to boot the unit, but it will be missing the ethernet communications. This is probably a moot point unless you also have an IPMA, TCU, or other ethernet based unit on the bench also. Again, the HS-CAN pins 53, 54 in the existing APIM connector will need to be disconnected. The appropriate wake signals will need to be sent over CAN. This is for Sync 3 and should be similar for Sync 4, since you can get a Sync 4 unit to boot in a vehicle and connect via FORScan.

From above:
{{0x109},{0x00, 0x03, 0x01, 0x00, 0x00, 0x00, 0x00, 0x28}} // Accessory ON, Gear Park, Speed 0 - this needed or else the APIM will default to driving mode and will lock out many settings.

If the APIM does not get any message that indicates the ignition position, gear and speed it defaults to the “car is driving” mode and locks out some settings.

NOTE: There is a TSB published about the APIM/TCU/GWM Diagnostics and Repairs - 2021 Ford F-150.
NHTSA ID Number: 10184628
Manufacturer Communication Number: SSM 49379
Before attempting repairs for SYNC 4 system, Telematics Control Unit (TCU) or Gateway Module (GWM) concerns, dealers must complete workshop manual (WSM) diagnostics in section 415-00 for SYNC 4 or TCU concerns and 418-00 for GWM concerns. Do not attempt APIM, TCU or GWM reprogramming or replacement unless directed by a WSM pinpoint test. If the root cause of a concern is isolated to the APIM, TCU or GWM with all other possible causes ruled out, dealers must contact the Technical Assistance Center prior to performing repairs.

And this issue…
21-2097_f150_battery_discharge.pdf (636.9 KB)

Getting it to boot on the bench is not the issue, I’ve had that working for several weeks. The CAN bus message you referenced does not work for Sync 4 to remove the lockout, but it boots just fine.

Connecting with UCDS is the issue. I’ve tried with an SDLC/GWM and a standard OBD pigtail.

I also fail to see what an IPMB or TCU will accomplish - none of those should be needed for UCDS to connect to the APIM itself.

Unless there is a hardware short on pins 53 and 54 on a Sync 4 APIM, to me that is just a software (AsBuilt) thing that needs to be figured out, potentially bundled with use of the GWM-A. Of course, just a huge hunch at this point on my part.

Either I’m missing something or I feel like we are talking about something different/different terminology.

Not true. This was removed from the platform altogether. It might be possible to replace it with a Firmware modification, but that would take a significant effort, and probably not worth it as the Sync 4 architecture was changed to delete it.

Did you boot the unit successfully with no restrictions? If so, what was the CAN message?
This shows that the ethernet is not responsible for APIM boot. It also shows that another signal is needed for Sync 4 to boot without restrictions, or thinking the vehicle is in motion.

Use FORScan 2.3.44 test version. It is proven to communicate.


If this is the case, then I don’t see how it will ever work without a hardware interface in between the APIM and the rest of the vehicle.

While it may be fact, I’m hopeful that’s in fact not true and there is a compatibility mode value in the AsBuilt.

I have not been able to boot with no restrictions, but it does boot fine with the following message:

0x44, 0x88, 0xC0, 0x0C, 0x10, 0x04, 0x00, 0x02

Using an STM32. No additional modules are needed.

It’s possible the GWM-A (or lack of) has something to do with the restrictions.

There are 2 other CAN-Bus connections and an ethernet connection for the APIM to the GWM. The one that was deleted was only for the PCM and BCM communications for the APIM. (And some other things depending on the vehicle model.)

Excellent. Thanks.

This is what I’m suggesting the GWM-A may be able to help with. Again, just a hunch as I’ve not had time to really dive into the 2021 workshop manual/wiring diagrams to fully understand what the GWM-A does besides help broker the new Ethernet connections.

I just pulled the wiring diagrams for 2021 F150, and it actually does look like the GWM-A connects directly to what is now referred to as the Remote Data Link connector, and the GWM-A does have all of the CAN Bus connections on it. I am seeing no reference or wiring diagram for a SDLC for 2021. The naming of “remote” data link connector makes sense as the OBD port is no longer “smart”, it relies on the GWM-A, from what I can tell from the diagrams.

The Remote data link connector has two sets of wires for DIAG CAN networks, which connect to the GWM-A. the GWM-A then handles all of the CAN traffic to the various modules, and ethernet to those modules that are equipped.

What’s odd, is the wiring diagram refers to the GWM-A, while all of the documentation just references GWM, which just adds confusion in my opinion. There is no wiring diagrams for a regular GWM.

I’d post more diagrams, but it looks like I am not tenured enough on the forum to post more than 1 attachment.

That diagram shows the replacement of the HS1-CAN and HS2-CAN networks on the Data Link Connector with the gateway subsystem (for lack of better terminology) using the same pinouts as the old networks on the existing (slightly revised) DLC, be it remote or smart. This looks like it could be acting as a protocol translator, just a guess. This looks like the same physical architecture used in the Edge/MKX/Nautilus model lines.
The DLC has gone by various names over the years, probably to distinguish it due to changes in architecture or what not.
This example below of the DLC is associated with the CGEA 1.3 version GWM. It is not this way on Ford vehicles not using CGEA 1.3 or above. There is a new GWM used in the F-150 vehicles, MR3Z-14F642-A is the service number. This could be the GWM-A, but this is not specified in the parts listings that I researched.

Can you post the GWM-A connections of the CAN-BUS networking?

Here are the other diagrams (all for 2021 F150).
Remote DLC:

Connector C2431A at the GWM-A

CAN Bus layout showing the GWM-A interfacing with all of the CAN Bus

Here is a picture of the GWM-A, which replaces the GWM/SDLC found in 2020-previous F150’s based on the above wiring diagrams, as well as the documentation I have posted links to below. I will be trying to hook mine up on the bench in the next week or so to see if there is anything of use by interfacing it on the CAN Bus.

Regarding the MR3Z-14F642-A part, my research shows this is for 2015-2020. Unless I’m missing something, there would be no benefit to purchase this for my 2018 F150, as it’s simply a revised part number that would serve the same function - I’m assuming it has updated calibration, but nothing that would support the newer architecture that Sync 4 uses.

If you’re interested in some light reading, here are the documents for the CAN Bus and Ethernet operations. The CAN Bus document goes into detail regarding the GWM-A being the only GWM in the vehicle, etc.
CAN Bus: