Gen 3 Modem/TCU unresponsive ... unable to remove previous owner from FordPass app

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Antho

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Thanks for posting the pictures. I would also go ahead and reset the GWM and try clearing the DTC codes again. after you have the TCU plugged back in.
 
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leonardopessoa

leonardopessoa

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Final update: @Antho provided me an incredible support and helped me debug it every step of the way, even being my first time touching Forscan/OBD, fuse boxes, etc.

Issues in order of fixing:
  1. Missing TCU fuse... micro3 5A fuse 8/9 was not there. Previous owner likely removed to prevent any communications with Ford servers
    1. Was discovered after I connected Forscan and caught errors stating problem communicating with TCU
    2. Checked passenger side kick fuse box and ... voilá!
  2. Corrupt/wrong TCU As Built data...
    1. Restored Factory AB through Forscan, running the TCU As Built Data module configuration, clicking Load factory AB and Write all.
If you followed my journey, it's been 7 months since I've purchase this truck, many dealership visits with wrong answers only (replacing TCU twice, rewiring, you name it) when all I was missing was a fuse and factory configuration. It's saddening to see the level of assistance two dealerships provided me and heartwarming to find solace here.

I do really appreciate his attention, dedication, and anyone else in this forum. I'm signing up to be a supporter immediately.
 
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FordTechOne

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Final update: @Antho provided me an incredible support and helped me debug it every step of the way, even being my first time touching Forscan/OBD, fuse boxes, etc.

Issues in order of fixing:
  1. Missing TCU fuse... micro3 5A fuse 8/9 was not there. Previous owner likely removed to prevent any communications with Ford servers
    1. Was discovered after I connected Forscan and caught errors stating problem communicating with TCU
    2. Checked passenger side kick fuse box and ... voilá!
  2. Corrupt/wrong TCU As Built data...
    1. Restored Factory AB through Forscan, running the TCU As Built Data module configuration, clicking Load factory AB and Write all.
If you followed my journey, it's been 7 months since I've purchase this truck, many dealership visits with wrong answers only (replacing TCU twice, rewiring, you name it) when all I was missing was a fuse and factory configuration. It's saddening to see the level of assistance two dealerships provided me and heartwarming to find solace here.

I do really appreciate his attention, dedication, and anyone else in this forum. I'm signing up to be a supporter immediately.
Glad it turned out to be a simple fix! I can’t believe the dealer replaced the TCU without even checking whether it had power! :rolleyes:
 
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leonardopessoa

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So I had a professional sound installer replace the disastrous installation that came with the truck and he thought it could maybe address the TCU issue since he never had an issue before in any other installation he had done. That didn't fix it.

I now have also the pre-collision assist warning going off (and eventually break-checking people on the highway) randomly. Took it to Lebanon Ford instead and... guess what? They say they need to replace the TCU AGAIN and would need to remove my sound installation.

Called my sound installer and he said there is no need to touch the sound wiring apart from disconnecting less than a handful of cables if at all to access the TCU. My service advisor doesn't want to work with my sound installer.

WHAT IN THE WORLD AM I SUPPOSED TO DO? Why are people so square? I understand the liability question, but it would be incredibly helpful if the Ford mechanic would just get on the phone for 5 min with my sound installer and sort it out - maybe it is just unplugging 5 cables to reach the damn TCU. If they figure it has to be disassembled, peace, but at least try. @FordTechOne any thoughts?
The pre-collision assistant issue has now been fixed too but I can't tell what did it. Best guess is TCU update @Antho provided me?
Why wouldn't the dealership update software every time if you agree to it? Or at least for weird bugs like this when you randomly get an error code... try updating software first, if that doesn't do it, test hardware/sensors next.
 

Antho

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The pre-collision assistant issue has now been fixed too but I can't tell what did it. Best guess is TCU update @Antho provided me?
Why wouldn't the dealership update software every time if you agree to it? Or at least for weird bugs like this when you randomly get an error code... try updating software first, if that doesn't do it, test hardware/sensors next.
The dtc you had was for a camera alignment. They may have calibrated it.
 
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