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Looking for someone that has a '20 or '21 that is up to date with all software updates and has successfully added a 3rd key fob without going to the dealer.
I have a '21 HTC Z51 and I am trying to program a 3rd key fob. The owners manual for a '21 has the details of how to do this, but I cannot get it to work. And the owner manuals of newer C8s do not include this process, so I'm wondering if a firmware update on my '21 removed the ability to self-program a new fob.
The issue is compounded by changing part numbers. My original fobs are both 13538853 (7 button for HTC). But if you try to order a new one for a '21 from GM, different part numbers are shown to supersede the original, and not all say they will work on a '21. Many sites cross reference to 13554501, but the fitment info says it is only for a '23. I ended up with 13547766, which shows for 20/21, but I cannot get it to program. Could be the wrong fob, a bad fob, or a fob that has already been programmed (I read somewhere they cannot be re-used?). Anybody?
Last edited by new_hampster; Oct 4, 2023 at 05:15 PM.
Reason: signature
I have a 2021 C8 and bought a fob from someone on Ebay. I found out later that once a fob is programmed to a car, it CANNOT be reprogrammed to another car. If you want a third fob, you have to buy a "virgin" fob from the dealer.
What does a virgin fob cost, and what does it cost to program it?
I don't know how much a new FOB will cost (Check with your dealer) but the C8 owners manual gives instruction on how to program it (attached). I took this from my 2021 owners manual. When i brought the FOB I bought off of eBay I tried to program it myself. When I failed, I brought it to the dealer and asked them to program it. After a number of tries, I think that they called Bowling Green and found out that the FOB couldn't have been programed to another vehicle.
I have a 2021 C8 and bought a fob from someone on Ebay. I found out later that once a fob is programmed to a car, it CANNOT be reprogrammed to another car. If you want a third fob, you have to buy a "virgin" fob from the dealer.
I think a dealer CAN reprogram a fob. But no, the owner can't.
I have a 2021 C8 and bought a fob from someone on Ebay. I found out later that once a fob is programmed to a car, it CANNOT be reprogrammed to another car. If you want a third fob, you have to buy a "virgin" fob from the dealer.
This one is supposed to be new - it looks new with stickers and all, but I guess I have no way of knowing. I'd still like someone to confirm that they have actually done this on a '20 or '21 with the current software updates. The process was removed from the owners manual beginning with '22. A software update could have changed the way this works on my '21, so for all I know even if I have a 'new' one, I will still have to take it to the dealer for programming. That's OK if it comes to that, but I'd like to know.
Now that I think about it, I did add a fob. I lost one of the originals, had a dealer program a new one, which ended up as fob #3, rather than 2. That one wasn't for an HTC, so eventually I ordered a new fob with the HTC buttons, and programmed it myself as #4. But I really wanted it to be #2, for memory purposes, so I ended up having the dealer reprogram all three of them. I followed the procedure in the manual, which requires both working fobs to be in the cupholder, IIRC.
I have a '23 HTC and decided to buy a third fob as a "failsafe" plan on long road trips. I ordered it from an online GM Parts Dealer and followed the instructions in the forum sticky to program it myself. As I recall, the two working fobs had to be in the car and the new fob placed in the rear cupholder. It succeeded as #3 and functions perfectly! HTH👍
This one is supposed to be new - it looks new with stickers and all, but I guess I have no way of knowing. I'd still like someone to confirm that they have actually done this on a '20 or '21 with the current software updates. The process was removed from the owners manual beginning with '22. A software update could have changed the way this works on my '21, so for all I know even if I have a 'new' one, I will still have to take it to the dealer for programming. That's OK if it comes to that, but I'd like to know.
If you followed the instructions exactly in the owner's manual, but your fob wasn't programmed to your car, I would conclude it likely was not virgin.