2021 night edition third brake light

[Arth]

We actually need someone that has a functional digital rear view mirror to de pin the Lin Bus wire from xy340a (or the mirror connector itself) to see if the image won’t come up. Maybe @Arth or @jdmdc5teg06 can help out with that, if they’re willing.

I don't know if I've got a tool to de pin the connector. I assume we are talking about that 3rd wire in the mirror harness that isn't power or ground.

 

[Jimmy07]

I don't know if I've got a tool to de pin the connector. I assume we are talking about that 3rd wire in the mirror harness that isn't power or ground.

Correct. This would actually be the easiest connector to remove it from temporarily. It’s behind the panel on the side of the glovebox -

Basically, you slide the blue lock out, and stick a paper clip, or similar, in the hole above the terminal to pry up the locking tab to be able to pull the wire out- https://ecat.aptiv.com/docs/default..._33265159_cus73_s01-pdf.pdf?sfvrsn=94a7d4d1_0

 

[Arth]

Correct. This would actually be the easiest connector to remove it from temporarily. It’s behind the panel on the side of the glovebox -

Basically, you slide the blue lock out, and stick a paper clip, or similar, in the hole above the terminal to pry up the locking tab to be able to pull the wire out- https://ecat.aptiv.com/docs/default..._33265159_cus73_s01-pdf.pdf?sfvrsn=94a7d4d1_0

Okay found the connector which pin?

 

[Jimmy07]

Okay found the connector which pin? View attachment 79144

Pin 6, orange/purple

 

[jdmdc5teg06]

Was just going to say that I just made it home from work and was going to disconnect that connector and see. Once the Orange/blue wire is disconnected that shouldn’t send signal to the mirror right?

 

[jdmdc5teg06]

Actually, I just remembered that I don’t even have the CHMSL connected since I’m doing the cargo camera install and haven’t wired that up yet

 

[Arth]

Pin 6, orange/purple

Okay confirmed disconnecting that wire killed my mirror. Pictures attached. I still got the icon to flip the mirror but no image.

 

[Daverous]

I'll hold my comments until the experts chime in, but wanted to hand out a big thanks for the assistance!

 

[ForTehNguyen]

people asked for videos and theres some on youtube

 

[Jimmy07]

Okay confirmed disconnecting that wire killed my mirror. Pictures attached. I still got the icon to flip the mirror but no image.

View attachment 79159View attachment 79160View attachment 79161

Thanks Arth.
Well....that’s pretty damning news for 2019-2020 owners. I don’t even think it’s a setting issue in the BCM that can be toggled on/off with AlfaOBD, since nothing needed to be changed on @jdmdc5teg06 2021 for it to work. I think it’s an actual BCM capability issue based on what firmware is flashed onto it.

 

[knightro84]

Well... darn. Not too big of a deal really - would have been nice if it worked but I mainly just wanted the 3rd brake light anyway for how it looks.

I’ll probably end up selling the mirror.

 

[ForTehNguyen]

so no ones gotten this to work in a 19-20 yet? I have a 19 Limited with Level 1 package so I have everything.

 

[Daverous]

Big time lame. I'm sure we'll find out more as time goes on as well. My only note is that when Arth pulled his pin the camera icon displayed as opposed to the cable break icon. Not sure how much relevance there is to that...

 

[Evank33]

Is there anyway to modify the bcm or upgrade it to get the camera to work?

 

[Jimmy07]

Is there anyway to modify the bcm or upgrade it to get the camera to work?

Possibly, with some type of MITM attack. It would be easier to pull a 2021 BCM out of a wreck, and manually configure it with AlfaOBD.

 

[z0n3]

@Jimmy07 if someone with a 21 adds this that currently has the auto high beams do they end up losing that feature after installing the digital mirror?

 

[Jimmy07]

@Jimmy07 if someone with a 21 adds this that currently has the auto high beams do they end up losing that feature after installing the digital mirror?

If you have high beams, but do not have the driver assist module in front of the mirror on the windshield (ACC and FCW features), then you will lose the auto high beam feature.

 

[Evank33]

Possibly, with some type of MITM attack. It would be easier to pull a 2021 BCM out of a wreck, and manually configure it with AlfaOBD.

I see infotainment sells "updated" bcm. Is there a way to update the firmware on the bcm to have the 2021 firmware? Would the dealer be able to do this?

 

[Jimmy07]

I see infotainment sells "updated" bcm. Is there a way to update the firmware on the bcm to have the 2021 firmware? Would the dealer be able to do this?

They’re just going to get the newest revision of the part number used on your truck based on it’s VIN, and restore your vehicle configuration to it. You’ll basically end up with the same BCM you have now. Let alone their ignorant prices. You can get a brand new BCM for ~$150, and configure it yourself with a crude bench setup

 

[Jimmy07]

Would the dealer be able to do this?

Sorry, missed this part of your question- the dealer can’t just obtain a particular firmware to flash to any BCM. But they can take a 2021 BCM and write your VIN, and restore your vehicle configuration to it.
Keep in mind there may be other unintended consequences to doing this, as a 2021 BCM may be cancerous to other features. IE...what if there are other features on 2019-2020’s that don’t jive exactly the same as 2021, etc.