2017 mkz 3G to 4g which tcu to buy?

Which tcu should I get? I see different suggestions. I am confused. some say JL3T - 14G087 - C% is the part number others a HJ5T-14G087-U#(# letter varies)Are there other part numbers I can look for? My original part was GP5T-14G087-DF. Is there something I should check on my car other than the current module?

This is the one you want. It’s a 4G.

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Or a JL3T-14G229, they are the same unit.
14G087 is made by Continental, 14G229 is made by Visteon

Is this the correct procedure?

  1. Delete car from Lincoln way

2.delete your existing car profile in Forscan and let it find your car again when you connect. This makes it build a new profile that includes your replacement 4G modem. You should see a TCU included in your module list once the car finishes connecting. Now let it save this new profile for you by clicking “yes” when it asks.

  1. Under “Service Prodedures”, do a forced reset of the “new” 4g TCU. Read and clear any codes that may remain in the TCU afterwards

  2. Add car to Lincoln way.

I read also do a TSB 22-2230 initialization procedure. Is this done with forscan?

Am I missing anything?

Look at F150Chiefs write up for this.
You need to be on the -CM calibration at the very least for this, the last 2 characters of the part number really don’t matter. As an example the one I dropped in my 2018 Fusion Platinum to replace the 4G H series (I wanted the TPMS display in Fordpass) was a JL3T-14G229-AJ, the actual board was a JL3T-14G229-CK in Forscan. The last 2 of the printed part number reflects the external mounting brackets of the factory assembly (which I didn’t need), the first 4 of the part number are the model it was supposed to go in. JL3T is an F150, they’ve interchangeable for the most part.

You CANNOT use your AsBuilt for this, look for one from a 2019 MKZ or Fusion, if this for the Hybrid that needs to match for the alarms to work. If this is for a PHEV you need to use one from a PHEV. The easiest way to get a VIN to pull an AB from Ford is to get one from one of the used car sites.

The H series is what Ford uses for the Energi 3G to 4G swap. no matter which you use you’ll also need a Ford PIFA antenna as well as a FAKRA Z F-F cable since the 3G didn’t use it, if you use a J series and are anal like me about DTCs you’ll need a second antenna set so that you don’t see a DTC for an open antenna port on the other connector.

I’m getting lost. I have a 2017 mkz black label with 3.0 and awd. So far I purchased the antenna from ford and the extension cable from aliexpress. If I understand you correctly I need to add a second antenna if I use a j series module. Is that for the hot spot and what type of antenna do I need? Am I correct in saying I need to get the vin for a 2019 or newer mkz to help get AB codes? Does the mkz have to be same trim as mine or just match engine and awd? Am I better off getting an hj5t-14g08-ye and if i understand correctly update to un. I guess I was under the impression that all I need was the hardware and to change some code in forscan. I tried looking at f150chiefs post but not sure which one i should be reading. I appreciate you taking the time to educate me

  1. The second antenna is quite literally a 2nd cell antenna it has nothing to do with a hotspot, if you don’t have a Ford PIFA connected to the second port you’ll have a DTC code thrown on the TCU for open port. It works just fine with 1 antenna connected to the primary purple port
  2. The AB has the platform config in it, your current factory one is for a 3G equipped unit, the last step of wrapping the whole thing up once you get the TCU talking and authorized is to load the AB from a newer year of the car into it (this only is loaded into the “new” TCU) followed by a ForScan module reboot. So in your case find a 2019 Reserve (doesn’t need the same engine, and the reason I say 2019 is that from my experience so far doing these on 2017/2018 is that I’ve had random failure to wakeup issues if I use a 2020), you can pull the AB from https://www.motorcraftservice.com/Asbuilt/ using the VIN.
  3. Since you don’t have a Hybrid/PHEV I would use a JL3T-14G229 or 14G087 as it will be easier to update the calibration/firmware via ForScan (make sure you have a good adapter like an OBDLink EX, the firmware update takes 45-70 minutes with a good adapter). I have used LS7T & KS7T units but with these you have to downgrade the firmware to the J series and it just makes for more work which you don’t need.

Here’s the link to the Ford doc for the 3G to 4G TCU update so you can see what you’re getting into, you can use either the patch PIFA antenna in the doc or use the metal box one that is used in the 2018+ production. The only difference is the patch requires a FAKRA Z M-F extension while the box uses a F-F.

Ok this is making it through my thick skull. I think I have the hardware part set I will get the JL3T-14G087-CM (local pick and pull has one from 2019 navigator)Two cables to connect the antennas and two antennas the flat ones from the kit which is NL1Z-19A390-A. I have download a ab file from a 2019 3Ln6L5Fc0hr646651. The software is where I am still sketchy on.
Once hardware is installed remove car from my Lincoln app then read car in for scan creating new build with 4g tcu. Do I do a force reset or upgrade tcu? Then how do use the an file from the 2019 to update my 2017? Final step is add car to my Lincoln app?

Here’s my process once I have the new hardware installed, take a read of F150Chiefs doc pages 5-7.

  1. Do a master reset on Sync3, this will remove access to the car in the Lincoln/Ford app. It also removes the TCU registration (which when you powered it up was for the VIN for that 2019 Navigator).
  2. You need ForScan 2.4.x with an extended license and a good adapter IF the firmware at level isn’t CM or higher, 2.4.x will let you update the firmware. You’ll need to leave the engine running, turn off the 30 minute idle timer in the cluster, while the firmware is running unless you have a GOOD battery charger which would allow you to just leave the ignition on/engine off (if you do this turn off everything (headlamps, HVAC, radio, dome light, etc before you start the firmware update). Make sure you have the PC/laptop plugged into AC power.
  3. once the flash is done, follow F150Chief’s doc to get the TCU into factory mode, etc. Once it completes and go to waiting for authorization, go into the Lincoln/Ford app on your phone and try to add the car back in, sometimes it can take a bit to get the authorization screen in the car.
  4. Finally, now that you have the car showing connected in the app, load in the AB your downloaded from the 2019, save it and write, once it finishes go into the service tab and hit the TCU reboot

It usually takes an hour or two for the TPMS to show if your car has the ability to shows the tire pressures in the cluster, you should be able to lock/unlock/remote start within 10 minutes or so of the TCU reboot.

I’m having a hard time find the F150chiefs doc what is it called?

Link to the pdf is about 3 posts down

This is all way more complicated than it needs to be. Just buy a J TCU series and you will be fine.

I am leaning on getting a j tcm. Any advice on steps or the ones above sound right?

JL3T - 14G087 or JL3T - 14G229, the last 2 letters in the part number (eg -CR or -AJ doesn’t matter as it reflects things like the external installation bracket, this is an factory assembly line part number not a service part number).
The two units are functionally the same and have the same hardware, the difference in the last 3 digits is the identifier for what company made the part for Ford.
087 Continental AG
229 Visteon