[djcwardog]

I looked into the parts for a 2021 Camaro. Here’s what I figured out so far. Different part # for the 2019+ HUD itself. The two plastic dash trim covers didn’t resolve for my car, so probably will be cutting out holes. The HUD Switch and its bezel both have superseded part #’s. I’ve augmented the original post below with the details I’ve uncovered in my research.

HUD – (for 2018 and earlier) 84016314; for 2019+ 84673166 $374.08
HUD Bezel “Trim Cover” - 23168369 - This goes around the hole in the dash $22.64.
HUD Display “Switch” – 23193704, superseded by 84428043 $55.14
Display Switch Bezel “F Plate” – 23197097, superseded by 84499224 $11.71.
I got all four of these in one eBay auction from a 2019 ZL1 donor car.

HUD Bolt “Bumper Cover Bolt” - X 4 – 11589012 $0.85, $3.40 for 4
HUD Nut “Combo Lamp Assembly Nut” - X 4 – 11609759 $3.62, $14.48 for 4.
I got both the above from TotalGMParts online which an Autonation dealership in Florida.

LVDS (USB “Cable” for X2) – 23390635 $67.94
OEM Lead with “Connector Kit” to splice X1 pin 1 to IPC x1 Pin 21. The old part was PT3779 for a 13576542 which was superceded by newer PT2558 for a 19368548. As best as I can see, these two are the same HUD X1 Connectors that come loaded with 8 wires for $40.50.
3 button switch “Connector Kit” PT3130 / 19300398 comes loaded with 4 wires for $37.89.
I found all three of these on Amazon Prime for a great price, almost $40 below the total for the three prices above with free Prime shipping.

I also ordered in a lot of 50 of the 0.64mm (female receptacle) terminal pins for my parts drawers just in case I needed them. These showed as discontinued at Mouser but I found them available at Newark.com, part # 928999-1.

That left me with:
Upper Dash Cover - 84124213 for the 2017-2018 Camaro only. For my 2021 it appears I’ll have to hope for the hole outline on the back and cut it out carefully as seen in the thread.
Front Trim Panel – 84225815 for the 2017-2018 Camaro only. This panel has the hole for the 3 buttons controlling the HUD. (Same - I’ll need to cut it out.)

[Nitro66215]

Nice. Have you confirmed wiring?

[djcwardog]

I got my HUD and switch from the donor 2019 ZL1. My order from WAMS also came in. They sent me a pre-programmed 2021 V8 uplevel cluster with the HUD enabled. Not shown, but I also got their audio upgrade, from IOS to IOT. Factory nav, wireless CarPlay and Android Auto, and HD radio come with that. The factory nav will be viewable in the uplevel cluster.

The photos show a bit of what’s to come. I will carefully inspect the cluster harness for wire color and pin location compared to the wiring diagrams in this thread to be sure that they didn’t change something for 2019+ cars. Something tells me that they didn’t now that I can see the back of a 2021 cluster. Mouser now shows the .64mm connectors as discontinued but I was able to find same-spec parts from Newark. With the cluster, HUD and switch all placed near each other, pins exposed, you can see what will happen. The large connector in the cluster will receive one new wire and have two other existing wires tapped into for power and ground. The thread shows pins 19, 21 and 23 as what we are dealing with. The HUD takes an 8-pin connector but uses only 5 of the 8 pin locations, three left unfilled. The switch has a 4-pin connector. For the LVDS (USB cable for X2) - part # 23390635 you can see that they make it impossible for you the reverse the cable when you plug it in. The plugs will only go in where intended as they’ve mirror-imaged the outside plastic connector - and each mating receptacle in the HUD and the cluster - that surrounds the actual mini-USB jack.

I should not have to worry about tapping into CanBus wiring like the folks did to integrate IO6 audio information displays into the cluster, as the newest cars use IOS/IOT audio. My harness has a pair of wires for Ethernet + and - instead of the total of 4 wires for CanBus like the 2017-18 cars.

[djcwardog]

As I work through a summary of what wires go where, I saw this in the thread at Post #29: “Do not complete the assembly until you fully integrate the 8 pin wire. You have 1 wire going from X1 pin 1 to the instrument cluster X1 pin 21. I purchased a pack of terminals (listed in the parts list) and crimped the wire direct so that it can go into the cluster easily. The power wire was T-tapped off of the Red/BU wire in the instrument cluster X1 pin 7. Ground was T-tapped off of the cluster as well. X1 pin 19.”

The thread at Post #1 mentions that X225 pin 22 routes power to the HUD unit when it comes that way from the factory. For the retrofit, I think the Post #29 info is what we should follow.

UPDATE - see below, but a 2020 Camaro would take HUD power by tapping into the cluster harness at pin 7. Pin 23 of P16 (the 32-pin HUD X1 connector) is not occupied in either the 2017 or 2020 cars.

I took the photo from above and tried to map out what will go where - a visual representation of the wiring diagrams and the words. The photo also reflects power from the cluster coming from cluster P16 X1 pin 7 to the HUD P29 at its pin 6.

By using the pre-loaded (with wires) connectors I can use a small electronics “pin puller” to withdraw the wires from P29 at pin locations 2, 5 and 7 where there are not supposed to be any wires on that connector. It should have just 5 occupied of 8 pin locations. That will make the wiring bundles smaller when I go to use fabric tape and zip ties to end up with a neat and tidy “factory-ish” harness behind the dash that connects the cluster, HUD and HUD switch to each other. I can use one of the three wires I pulled to become the input pin 21 in the big P16 connector. I’d simply use another solder butt connector to join the wire coming out of P29, pin 1 to the newly locked in wire coming from P16, pin 21. Do that and I can avoid having to use any of the 0.64mm female pins I bought as spares for the parts drawer. I wrote in the wire color designations below as a means to double check my pin outs. Of course, the loaded wires from the P29 and S27 connectors seem to all be white, so route them carefully!

[2SSRS@Gen5diy]

Does any one want a P&P harness for most of it?

[2SSRS@Gen5diy]

From what we see the wiring is referent between 2016-2018 cars and 2019 up cars, that's all.

[djcwardog]

I’ve accessed the service info and diagrams as suggested. Not a bad resource for $15 for 24 hours of access! Not everything came up for my 2021 Camaro, but I did see everything needed for a 2020 Camaro. While I was in there I took a look at the 2015 and 2017 Camaro for their cluster and HUD interface. Definitely changed after 2015. From a 2017 to a 2020, it looks like S27 and P29 may still be the same, but the P16 cluster wiring is a bit different. Here are the three wires:

Power definitely is taken from the 15 amp fuse which runs a RD/BU 0.5 (thicker) wire to pin 7 for “Secondary Fused Battery Positive Voltage 32”.

Looks like the ground is still a BK wire at pin 19.

Pin 21 is still used as a two-way data relay GN/BK wire between the HUD and the cluster, but it’s now called “Instrument Cluster LIN Bus 1”.

Now I have to hope that they didn’t change things up from 2020 to 2021. Anybody know if a 2021 HUD does things that a 2019 or 2020 doesn’t? Perhaps it was just when they went from B/W to color a few years before? By the way, I checked out a 2019 Yukon 4WD (my wife’s ride) and its HUD/cluster wiring seems similar to the 2020 Camaro and why not? Apply the tech across the platforms!

[WhyUMad1LE]

How do you get to the HUD? Mine has a rattle that's driving me crazy.

[WhyUMad1LE]

Originally Posted by djcwardog

You may have to follow the steps earlier in the thread to remove the dash trim pieces so you can tighten down the four fasteners that secure your HUD in place.

As I feared. Well I got the gauge cluster out but need a special tool to reach the bolts by the windshield, going to look for that now..

Does the glovebox have to come out as well? It shows its removal in the pdf but I don't see why it would need to.

[djcwardog]

You take off the entire top of the dash as well as the wide piece that surrounds the cluster. The OP lays this out in detail and he also provides a .pdf link for the dash disassembly needed. [UPDATE - I also cover this in my 2021 DIY, linked below.] Do all that and it appears that we’re running the HUD bolts straight down into the special nuts. In your case, just tightening what’s already there.

[djcwardog]

I snapped a photo of the bolts and nuts that correlate to the parts listed by the OP.

BTW - Not HUD-related but the bolts look identical to the four that secure the lower dash cover on the passenger side. This is the piece that you have to remove in order to access the IOS radio when you want to upgrade to the IOT radio. Order a few spare bolts now just in case you lose one or more of those if doing the same IOS to IOT upgrade.

[Nitro66215]

[djcwardog]

I finished mine up. The HUD Switch appeared to be inop but the HUD works fine, shows turn arrows in the navigation function along with speed and speed limit. The HUD option in the cluster allows me to rotate the HUD view properly. However, the three HUD Switch buttons do nothing and my dimmer knob appears to no longer have an effect to dim the dash at night. I checked and triple-checked my wiring between the HUD and the HUD Switch - only 4 wires - and I confirmed it again anyway at the switch. It’s easy enough to pry out the dash surround there without having to unscrew anything. Tonight I tried dimming the dash after I unplugged the HUD Switch again. Once I pulled the red pin protector out of the 4-pin connector and jiggled that a bit after plugging it back in, the switch started to work. It was intermittent, so the switch has to be bad. A new switch is inbound.

[djcwardog]

I took the OP’s work and augmented it with a few more photos and details on getting stuff out. For the wiring and parts we care about, although other wires may have moved or gone away in the 32-pin cluster connector, this retrofit in a 2021 Camaro still seems to follow that of the 2017 Camaro. I confirm also that I get a color HUD display, so the 2019 HUD that I bought as a used part still seems to be fine for the 2021 cars. Hope this helps others!