2016 MKX upgrade TCU FOR 4G

ATT eliminated 3G, and Lincoln has paused the dealer program to swap the TCU. A user on the LincolnMKX forum was successful with a swap he did. I tried to do the same, and used the same numbered unit he did. I seem to be stuck, though - Forscan sees a TCU and can read values from it, but a TCU trst fails, and SYNC 3 shows no modem ESN on the screen. Of course, I can’t do what was intended - restore the remote start and lock features in the App. When I add he car via VIN, no activation choice is made available. Maybe the TCU I have was configured differently than the successful user? Here are some images - the numbers for TCU and Strategy don’t seem to match, and the readings show key as “key off” when it is on…

Will post the readings in the next post as I’m only allowed one image…

Any suggestions? Might I need to downgrade the TCU firmware? If so, where do I locate the files needed and how to go about that? Thanks!

Here is the thread for the guy who was successful - he has not reponded to my queries there yet:

And here are the readings showing it’s sort-of working - key is on, but shows off here - maybe that’s not an issue - anyway:

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If you have not changed any of the AsBuilt in the TCU or did a full factory reset (which requires you to change AsBuilt bits in order to do so), this is the likely cause. This TCU upgrade is not a plug and play thing.

Post your AsBuilt from the TCU and someone can give you some guidance where to go from there.

So thanks - nothing was changed when installed - here is the “start” of the As Built - this TCU seems to show more lines at “754-” than others, so this screen cap is partial - I can scroll down and do a capture of the rest?:

Your voltage is really low also.

The first question: What Sync version is in the APIM on your 2016 Lincoln MKX? What is the part number of the APIM? Is this modem equipped with wireless hotspot? Do you plan on using the hotspot? The answers to these questions will determine if this modem will even work for you.

I read the thread you attached. There are probably features and functions of his TCU that are not correct or not working…unless he did not post all of the steps and information in the thread. First thing: the JA1T-14G229-AJ is a different modem than the KT1T you are using. It is possible to use the KT1T modem in your 2016 MKX, but you have the wrong Calibration Level in the TCU. The Calibration and Strategy files will need to be changed, reprogrammed, then the asbuilt will need to be adjusted for your vehicle. The TCU is presently calibrated for HS4-CAN, your vehicle does not support this, and the JX7T Strategy file will not work with a 2016 vehicle at all. Also, it is possible that your APIM will not support this TCU, especially if the APIM is a G-series. The G-series APIM will not support the hotspot, and some other features of the TCU.

This TCU shows it is in “Authorized Mode”, which is probably left over from the last vehicle it was installed in, which would be a 2019 Lincoln based on the part number. That TCU is still tied to that VIN in the FordPass system. To use this TCU, you will need to disassociate the TCU and the donor vehicle.

To solve these issues, you must downgrade the TCU firmware to:
Calibration Level: JL3T-14G087-CR, -CS, or CT
Strategy: JL3T-14G139-Cx
ECU Config: JL3T-14G144-Cx

Then, you will need to make the appropriate adjustments to the APIM, BCM, IPC.
APIM, Sync 3.2+:
Instruct the APIM there is a TCU.
7D0-02-02 xxxx *xxx xxxx, from 8 to 9.
Instruct the APIM that the TCU is hotspot capable, if so equipped.
7D0-02-03 *xxx, from 0 to 4.

Vehicle must be equipped with and programmed for factory remote start.
Enable Remote Start:
726-22-02: xxx1 xxxx xxxx
Remote Start: 0=disabled, 1=enabled

Tracking and Blocking Module (TBM)
726-49-01 x*xxx xxxx xxxx
TBM Avail Cfg: 0=absent, 1=present

Adds Remote Start menu to instrument cluster.
720-02-02: xxxx Axxx

Load a new asbuilt into the TCU that is compatible with your vehicle.

Once the adjustments above are completed and the firmware has been downgraded, the APIM should have communications with the TCU. If it does not, the authorization will not work.

You will then need to unregister the modem on the FordPass system. This will require wiping the TCU registration with the previous vehicle and registering the unit to your vehicle. This will require the use of FordPass on your phone paired to your vehicle, and FORScan. Keep in mind that whenever you are working with the TCU changing parameters in the asbuilt for registration that the vehicle must be running, engine on. I can see that the pics above indicate the engine is off.

There is a specific procedure to follow once all of the requirements and adjustments above are completed to authorize the TCU for your vehicle.


Thanks so much for the detailed analysis - this is exactly the help I needed…

Currently running SYNC 3.0, and have no need or desire to run a hotspot in the car, so assuming that eliminates a lot of work?

Here is the current APIM info:

So seems like I need to downgrade the TCU - where do I locate the files needed to do that? I have seen reference to a ford site but when recently visiting these links, it tells me I need a username and password. Once downloaded, can I flash these using Forscan?

The car was supporting remote start, etc with the 3G TCU unit, so was enabled from that perspective - I can verify the other module settings to be sure those remain enabled.

The only things I would like to restore are the remote start, remote lock, and possible oil life/tire service indications, all of which were working until the ATT shutdown in February.

Thanks so much for your assistance!

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Not so much a lot of work but a lot of headache. The Sync version and firmware version of the APIM should work.

Ford recently changed the access for those resources and requires an account.
I will PM you some info for the files and firmware programming.

With the amazing help here, I got this fully functional… Thanks!

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