Significantly Decreased 2018 Yukon XL FOB Range

[Dalien]

I'm confused?? I went to the dealer to get a replacement FOB Receiver / Antenna for my 2018 Yukon XL. The dealer sold me the 315 Mhz antenna part # 1358-6853. I went on Rock Auto and it lists the same part for my vehicle. Whats confusing is that the dealer showed me that the antenna is located on the passenger side rear pillar (3rd pillar). I was looking at Nickfire20's post which shows it under the roof liner with a short wire coming off the antenna and plugging onto the side window wires. My vehicle has the same wire coming out from the roof liner. The antenna that the dealer sold me does not look the same as the one in Nickfire20's post. Do I have the right part?? I haven't taken the panelling off yet so I guess it's possible that a 2018 has it located on the pillar and the wire that is attached to the side window is long and plugs into the antenna I bought. The dealer and Rock Auto both say that the antenna needs to be programmed but other posts on this site say that they plugged it in and it worked. Any clarification would be greatly appreciated.
Thanks!

 

[Fless]

If you gave your dealer your VIN then you likely have the correct part. Which RPO code do you have, XL7 (315 MHz) or XL8 (433 MHz)?



Do your remotes show a frequency on a label or molded into the case? Have a remote FCC ID?



If you use your VIN when launching www.gmpartsgiant.com, you may have better luck finding part numbers.

 

[Dalien]

My remote has a sticker on it saying 315M so I'm assuming it is XL7. I thought the RPO codes are in the glove box but I could not find them. What puzzles me is that my vehicle has the same "9 Volt battery" looking connector on the rear passenger side window just like what Nickfire20 showed in his post but my new receiver/antenna doesn't have this wire/connector which makes me wonder if the dealer sold me one of the other antennas that are in the vehicle but not the one that deals with the long range door lock/command start. OR, as I mentioned before, maybe this 9 Volt connector has a long wire attached to it that leads to the 3rd pillar where the dealer says my receiver/antenna is located and plugs into the receiver/antenna that I purchased. I'm also puzzled if I need the dealer to program it or not?
Thanks for any input!

 

[Dalien]

It was actually Bob2C's post with the pictures. Funny thing is, he and Nickfire20 are talking about fob range and how this part fixed the problem but when I look up the part, it describes it as an amplifier for the AM/FM. No mention of anything related to remote door locks or command start, unless I'm missing something. The part # is

GM 84693389 Amplifier Assembly, Rdo Ant​

Any help would be greatly appreciated!!

 

[Jroby42]

It was actually Bob2C's post with the pictures. Funny thing is, he and Nickfire20 are talking about fob range and how this part fixed the problem but when I look up the part, it describes it as an amplifier for the AM/FM. No mention of anything related to remote door locks or command start, unless I'm missing something. The part # is

GM 84693389 Amplifier Assembly, Rdo Ant​

Any help would be greatly appreciated!!

Yep, that's the part that I ordered from RockAuto and fixed my issue.

 

[Dalien]

Yep, that's the part that I ordered from RockAuto and fixed my issue.

Thanks a lot for your reply. Ill order one too. Did you have to get it programmed or just plug it in as is? Did it greatly improve your fob range?
Thanks Again!!

 

[Dalien]

Thanks for your help!!
I replaced the part and my FOB range is back to normal.
Thanks again!!

 

[Flightdeck]

Thanks for your help!!
I replaced the part and my FOB range is back to normal.
Thanks again!!

2018 Premier **:
Just replaced my …3389 antenna because my 2 fobs with fresh batteries from different packs steadily reduced in range to the point I have to center console “slot” a fob to start.
Any other ideas?

Ive been to 2 dealerships, wa$te of time.

Prior to the fob fail I had 2 momentary total electrical fails 3 weeks apart at interstate speeds after sunset.
Sporting moment for the cardiac pressure. All systems recovered within 3 seconds.

Dealer showed no BCM faults, go figure.