2021 night edition third brake light

[Daverous]

Factory wheels and tires. Only saw the no fob once, but the tpms was all over. I'd lose one, or two, or all four at a time. I'll let them swap the hub Wednesday and see where it leads. Still no issues on my drive to work today with the factory chmsl.

 

[Ramjeep]

Anyone have any vids of the 3rd brake light? I ordered one but it's stall in process.

 

[securityguy]

Anyone have any vids of the 3rd brake light? I ordered one but it's stall in process.

Vids of exactly what?

 

[trithumb]

Anyone have any vids of the 3rd brake light? I ordered one but it's stall in process.

Take 4 screws out, unplug it, plug the new one in put screws in. Tadaaaaa

 

[knightro84]

Well, my mirror came in last week and I finally had some time to install it today. Unfortunately, I'm getting the same "error" as @Daverous. The harness on the mirror has way more wires than my stock auto-dim mirror had, and I'm assuming there is some additional wiring that has to happen to get this to work (perhaps also in addition to some AlfaOBD programming). I ended up buying the gateway bypass module from Infotainment, and the OBDLink MX+, just need to run out and buy a cheap Android tablet. Would really be interested to see what the truck-side mirror harness on the 2021 trucks looks like.




EDIT: for reference, this is the mirror-side harness on the 2019 auto-dim mirror:

 

[Daverous]

I was hoping yours would work. Bummer.

Resolved my tpms drop out with reprogrammed tpms and a new rf hub on Friday so at least my light works properly now. Kinda doesn't feel worth it to me without the camera though. Hopefully someone can snag a picture of their 21 mirror harness when they get a Second. The connector reference chart doesn't appear to have anything on those extra wires yet.

 

[Arth]

I was hoping yours would work. Bummer.

Resolved my tpms drop out with reprogrammed tpms and a new rf hub on Friday so at least my light works properly now. Kinda doesn't feel worth it to me without the camera though. Hopefully someone can snag a picture of their 21 mirror harness when they get a Second. The connector reference chart doesn't appear to have anything on those extra wires yet.

Here is what my 2021 looks like with the mirror.

 

[Jimmy07]

Here is what my 2021 looks like with the mirror.

View attachment 79102View attachment 79101

Thanks Arth, I was just getting ready to post this, too-

So, definitely is only using power, ground, and Lin Bus.

 

[Daverous]

Thank you! Now I'm even more confused.

 

[knightro84]

So in the upper right of the schematic - there is a digital rear view camera module. That isn’t some separate module is it? Or is that just the actual camera itself in the CHMSL?

 

[knightro84]

Here is what my 2021 looks like with the mirror.

View attachment 79102View attachment 79101

Does your mirror-side harness have all of the extra wires too? I guess it doesn’t really matter since the truck-side just has the three wires, but just curious.

 

[Arth]

Does your mirror-side harness have all of the extra wires too? I guess it doesn’t really matter since the truck-side just has the three wires, but just curious.

The reverse side does have extra wires yes but as shown only the 3 on the other. Something else I noticed, at least on my truck, the mirror is tied to fuse F48A under the steering column. Accidently blew it tonight (oops).

So I wonder if you guys really are just having a cable issue (Coax). The fact you are getting anything on the mirror at all means you've got power. When I blew that fuse I got nothing from the mirror. From what I can tell that's all you really need is switched power and the feed from the camera. I am 100% shooting into the dark here so I am probably wrong.

I haven't been following this thread all the way through but I could check other things to see if we notice anymore differences just tell me what everyone wants checked.

 

[UnloosedChewtoy]

If it wasn't so expensive, I would buy the components and bench test them before installing into the truck.

12v to the power wire, ground to the ground wire, coax to the 3rd brake light... all on the bench. See what works/doesn't work, if it worked at all, and experiment, see what would make it work (if anything). Maybe thats just my inner geek coming out.

 

[Evank33]

Have you guys tried messing with the FAKRA on the camera side. I know one person posted messing around with the cables on the mirror side to get it to work. Might be worth a shot. Or maybe order a FAKRA cable with the type A and type B connectors. I have the parts in the mail for my truck so once I get them I can weigh in more. Also if you have a Tazer maybe switch the CHMSL to yes.

 

[knightro84]

Have you guys tried messing with the FAKRA on the camera side. I know one person posted messing around with the cables on the mirror side to get it to work. Might be worth a shot. Or maybe order a FAKRA cable with the type A and type B connectors. I have the parts in the mail for my truck so once I get them I can weigh in more. Also if you have a Tazer maybe switch the CHMSL to yes.

I ordered my cable from Pasternack with an A connector on one end and B on the other. They were snug with no play.

I’ll try messing with the cable at both ends today to see what happens though just for S&G’s.

 

[Daverous]

So in the upper right of the schematic - there is a digital rear view camera module. That isn’t some separate module is it? Or is that just the actual camera itself in the CHMSL?

Appeared to be the camera on the chmsl to me. Not a separate module.

Also, for reference I've played with every side of the cable. Even removed the camera from the light housing and tried it direct. The camera has zero interface with the chmsl other than mounting. It simply bolts in. Same symbol with it removed. It's reading that it's there and changes from no camera to connection error symbol but won't display for some reason.

 

[knightro84]

I just played around with both ends of the cable for about a half hour with no change too. I also de-pinned the CBC pin on the XY340A connector on the passenger side behind the side dash cover so that theoretically all the mirror was getting was power, ground, and the camera and nothing changed. Would be interesting to see if it still worked on a 2021 without communicating with the LIN bus, but I’m not expecting anyone to depin that connector.

This is what shows up as soon as I flip the mirror to camera mode. The mirror symbol with the finger goes away after a couple seconds. @Daverous do you get that as well? From the videos I’ve watched of the mirrors that work correctly on new trucks, it just switches straight to the camera mode and doesn’t show this “message.”

Not sure why it’s uploading sideways.

 

[Jimmy07]

I just played around with both ends of the cable for about a half hour with no change too. I also de-pinned the CBC pin on the XY340A connector on the passenger side behind the side dash cover so that theoretically all the mirror was getting was power, ground, and the camera and nothing changed. Would be interesting to see if it still worked on a 2021 without communicating with the LIN bus, but I’m not expecting anyone to depin that connector.

This is what shows up as soon as I flip the mirror to camera mode. The mirror symbol with the finger goes away after a couple seconds. Not sure why it’s uploading sideways.
View attachment 79121

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.

 

[Daverous]

I got the exact same as you @knightro84.

 

[knightro84]

Ran my config on AlphaOBD... saved it as a PDF from Google Drive and I've attached here.