Let the hacking begin... (Model S parts on the bench)

[Domih]

If the MCUs are not rooted, the CIDs won’t respond to ping (maybe they will just a few seconds during boot).
Did you exchange just the displays? Maybe you need to check the connections. You can do it on the bench, the CID should boot fine.
Did you accidentally break something when removing the displays? Those wires are connected with latches that sometimes are easy to miss.
If it comes to that, I have a rooted MCU1 I could part of, with US LTE modem. I also have a Tegra board to spare with a good chip that will last forever. Although both of them are rooted, we would need someone to work on it and on your car (I normally work with @LayZ, who is fast, great, fair, reliable, honest, and anything you can think of). But I hope it’s just some silly sloppy connection.

They are not rooted. The display works fine on my other MCU.

I think it broke because I connected the display of the (newer) other MCU to the old MCU. The display of the old MCU works fine on the new MCU.
The wires are fine, I swapped them between both MCU's.

When connecting to car or testbench, the "12VOLCD" LED stays off. I already have the 64GB eMMC. I'm not sure how the eMMC can be the problem, after switching the displays

 

[cloneguru]

Assuming both are MCU1, the screens are interchangeable. The blue or green circuit boards on the back of the screen are just from different manufacturers but they are still interchangeable.

If both screens work and the MCU that isn’t displaying has already been upgraded to 64gb then I’d agree it’s unlikely to be an eMMC issue or a display issue.

Was a redeploy done with a swapped MCU? If so, the correct MCU would need to be installed then another redeploy.

There are 3 pairs of green/yellow lights on the CID main board inside the MCU. These are network link lights. One is the gateway, one is the IC, and one is the diagnostic. If nothing is connected to the diagnostic then you’d only expect there to be two pairs lit. Does the instrument cluster link come up? Or if you’re plugging in a laptop/desktop, does a link come up when connecting to the MCU?

The screen will not light up unless it’s woken up by a brake pedal or sitting in the seat or something similar even if functioning correctly so I wouldn’t use the screen not lighting up as an indicator of a screen issue.

 

[Domih]

Assuming both are MCU1, the screens are interchangeable. The blue or green circuit boards on the back of the screen are just from different manufacturers but they are still interchangeable.

If both screens work and the MCU that isn’t displaying has already been upgraded to 64gb then I’d agree it’s unlikely to be an eMMC issue or a display issue.

Was a redeploy done with a swapped MCU? If so, the correct MCU would need to be installed then another redeploy.

There are 3 pairs of green/yellow lights on the CID main board inside the MCU. These are network link lights. One is the gateway, one is the IC, and one is the diagnostic. If nothing is connected to the diagnostic then you’d only expect there to be two pairs lit. Does the instrument cluster link come up? Or if you’re plugging in a laptop/desktop, does a link come up when connecting to the MCU?

The screen will not light up unless it’s woken up by a brake pedal or sitting in the seat or something similar even if functioning correctly so I wouldn’t use the screen not lighting up as an indicator of a screen issue.

Thanks! Good to know they are interchangeable. They are both MCU1.

There has been no redeploy, there also hasn't been an MCU swap. I will check the lights.

The screen also doesn't light up when connected to car. Car displays "center display not available" and/or "park assist not available".

Is there any way to force the MCU into recovery mode and do a redeploy from there?

 

[Domih]

I also tried to connect to my car with Toolbox3, but for that my car needs to be connected to the internet, I now get the "Seceth unlock failed" notification. Does any1 know of a way to connect to the car when car can't connect to internet for obvious reasons?

 

[Domih]

So the Ethernet lights turn on (see leds marked with "1". Orange stays on and green blinks very fast.

Maybe the problem is with the red LED (marked "2")? It blinks and the text is "Q38"

 

[whitex]

They replace the whole tegra board. Tesla might be doing fine resoldering work because they might be running out of tegra boards, but certainly not at the SC level. They might take your broken board somewhere to fix it, and offer it to the next guy.

That is what they do - the replacement tegra board for the recall shows up on "refurbished" on the invoice.

 

[Domih]

What if I would place the Tegra board in my other MCU and install that one in the car? Or will I risk bricking both MCUs?

 

[M0rpH3x]

Are they on the same fw version? If so, it can work. If not, you’ll mess things up, but it will be undoable just by reinstalling the stuff back as it was.

Alternatively, you can try that, and if there is a fw mismatch, redeploy. @LayZ most likely can assist you, if you don’t know how to do it.

 

[M0rpH3x]

One thing: be careful when trying those things. A fw mismatch might mean no 12V support, so make sure you don’t kill the 12V battery.

 

[Domih]

Ok so my other MCU fully boots on the testbench, I took pictures of both MCU lights, maybe in there we can see what's wrong and others may learn from it aswell. First pic is of the lights of broken MCU, second pic full board of broken MCU, third pic of working MCU and fouth pic is booted working MCU

 

[M0rpH3x]

Check the alerts for mismatch between gw and mcu. Check the fw. If it’s the same, go for it.

 

[Domih]

Check the alerts for mismatch between gw and mcu. Check the fw. If it’s the same, go for it.

So put the Tegra board of the defective MCU in the working one and then check?
Or put the Tegra board of the working one in the broken and check if it boots?

 

[M0rpH3x]

Put the tegra board you want to keep in the MCU that works with the display and check. You’ll get a bunch of errors, because a lot of ECUs are missing. Look for a fw mismatch between gw (which is in the MCU) and the MCU itself (which would be the tegra board). If there are no complaints about that, you can try to put it in the car and see if it works, but make sure the 12V is accessible when you do this. Check again for mismatches. If you see the error “software update required”, most likely there is a mismatch and you need a redeploy.

 

[Domih]

I put Tegra board of the broken MCU in the working MCU and the working MCU won't boot. Will see if the broken MCU boots with the working Tegra Board.

What I can see: The 12VOLCD doesn't turn on, 1v2 media doesnt turn on and the D124 (or D125) led is red (forgot to take picture). Will connect broken mcu with good tegra board now

 

[M0rpH3x]

That tegra board works, right?

 

[Domih]

The broken MCU boots with the "wrong" Tegra board installed!!!! Can I put it in the car? I can't enter service mode and unlock GW because I have to disable alarm, but I can't disable it.

So my Tegra board/eMMC is broken. I'm kind of scared to put it in the car, because I also see the milage of the other vehicle

 

[M0rpH3x]

Ok, I’m a bit lost of what we wanted to achieve. Can we recap a bit? You were trying to fix the display, but it seems that the display is ok and that the tegra board is fried, correct?

Where did you get the other tegra board from? What about your certificates?

 

[Domih]

I own 2 model S with MCU1(P85 and P90D). 1 MCU(P85) stopped working after trying to swap the "leaking" display.

Now I took the Tegra board of the P90D and installed it in the P85 MCU and it boots.
I want to achieve 2 working MCUs ideally, but needed to figure out what's wrong first.

Most important is to keep the P90D in working condition, so I will swap the Tegra board back to the P90D.

At least I now know a little bit better what the issue might be, clearly in the Tegra board.

Thank you very much for the help so far!

The VIN displayed in the MCU is the correct one, but milage is wrong, AP information etc is wrong I'll post 2 pictures of the LEDs of working MCU 1.0 so others can compare

 

[M0rpH3x]

Ok, you need two things now:

- A new tegra board. Tesla won’t sell you one. You might look in ebay for one, or maybe in this forum. I have one, but I’m in the EU.

- A data/recovering guy to get your carkeys out of the broken tegra board. There are people in this forum that do that.

Worst case, you can’t recover your data, you lose app access, not sure about updates. You “might” be able to sort that out with Tesla, but my expectations are terribly low, from my personal experience. They hate tinkerers with all their hearts.

Let me know if I can help you with anything else.

 

[Domih]

Ok, you need two things now:

- A new tegra board. Tesla won’t sell you one. You might look in ebay for one, or maybe in this forum. I have one, but I’m in the EU.

- A data/recovering guy to get your carkeys out of the broken tegra board. There are people in this forum that do that.

Worst case, you can’t recover your data, you lose app access, not sure about updates. You “might” be able to sort that out with Tesla, but my expectations are terribly low, from my personal experience. They hate tinkerers with all their hearts.

Let me know if I can help you with anything else.

Thanks!
I'm also in the EU (Netherlands).

Will replacing eMMC fix it? Or do I have to replace the whole board? Maybe there is another way to fix it, if the eMMC went into panic/recovery mode or someting.