My GMC trailer light test functionality appears to have been removed or lost in the most recent update of the app - March 2025. I use this feature frequently. I called OnStar support today 3/9/2025 and they seemed confused regarding this trailer light testing feature. How do I get this trailer light test functionality restored in the app?

Hey Advisor_Jack, the issue is the words come out that OnStar cares…but in reality the only “care” is whether a customer sends in $$ every month. Possibly this was a low used feature, but I kind of doubt it. It was super convenient and I used it probably twice a week all summer. It impressed my friends too…now it’s gone. I’m pretty close to following Brad’s lead. What does it take for you to actually listen to your customers??

I too noticed this today. I connected to my trailer and went to run the light test in the app like normal and it is nowhere to be found. I chatted online with an advisor and they seemed to not know what I was talking about. They suggested I uninstall and reinstall the app. The trailering functions in the app were very helpful.

I too got seriously disappointed when I picked my boat up from winter storage and grabbed my phone to start the light test, only to find all the pro grade trailering features gone from the app. This is wholly unacceptable by GM to remove this feature. The worst part of it is that there was no notification…just gone with an update. I am seriously disappointed too. And I may also cancel my On Star service. I’ve had OnStar enabled on my vehicles since October of 1996…but as of late, my overall satisfaction with OnStar and anything software related GM is doing is waning. This feature was very valuable to me. Apparently nobody at GM bothered checking with users to see what they actually used. The other thing they took away was the trailering loading calculator. Can’t imagine this was expensive to keep in the app either…whole thing is consistent with the overall poor infotainment software experience in my Yukon XL. Not sure why I’d expect to lose a feature after paying $86,000 for a vehicle and then sending in $40 a month for an OnStar subscription. Cmon GM…do you even care about your customers?

Just found this same issue yesterday. The trailering features, especially the light test, might’ve been my favorite app feat.

MyGMC Trailer Light Test | OnStar Community

46 Replies

gonecampin1
New Contributor
7 months ago
A very convenient part of my gmc, especially when your alone and hooking up a trailer. Must be like their motors that they knew about and did nothing until now. This was a selling point for me when I bought my pickup. Think twice now about buying a gmc even though I love my truck.☹️
- Advisor_Ahmed
  Moderator
  7 months ago
  We know how frustrating it can be to lose convenient features like the trailering features in your myGMC app. Our team will document your feedback for internal review. Please let us know if you had any further feedback, questions or concerns.
Grizzzz
New Contributor
7 months ago
I've only had my pickup since last fall, but I never noticed the trailer light test being an option on the app. Do you have to be running and have a trailer connected for it to show up? I only ever use the app to remote start in the mornings so I've never checked it while the truck was running. Having this feature on the app would be awesome, I do use the light test pretty often.
MarkH2024
New Contributor
6 months ago
The F150 has leapfrogged the Sierra in a lot of ways this generation, but trailering (for now) is still better on the Sierra.
So why the h*ll would GM start tearing down one of the few advantages they have left? Blows my mind - I can't imagine the cost of maintaining that feature is more than the loss of even one sale, but they may have lost me over it. Disappointing to say the least.
- Advisor_Helen
  Moderator
  6 months ago
  Our team here does appreciate this feedback, and we have further documented it for internal review. Please know, we are only a private message away if you are currently facing any concerns regarding the mobile app. You can also send us a message if you would like to share any additional feedback moving forward.
  - Diveboss
    New Contributor
    6 months ago
    Advisor_Helen
    It appears the complaints for this have been coming in for more than a quarter of the year. Still OnStar by GM has not added the feature back to the app. I went to use it today and found it missing. No more Bovine Scat. Please push this issue to the top tier and have it added back to the app or more customer will be dumping their GM vehicles and OnStar.
BigGun3500
New Contributor
6 months ago
I was hoping by now this would have been resolved but it appears that it hasn't so I feel inclined to voice my dissatisfaction of not having this feature. It was a great selling feature when I purchased my 3500 HD Dully for the purpose of pulling trailers. I have to always connect my trailer by myself and having the trailer light test allowed for me to test and ensure that all the lights were working properly. Without this test feature it's just plug it in and hope everything is working properly. There have been several time when there were issues with the plug connection that were easily found with this test. You would think that both GM and OnStar would understand how much of a safety feature this function was making trailering safer for everyone on the road where lives count. You have the software for the function already written so just put it back in the application.
Don3500
New Contributor II
6 months ago
Apparently GM just released yet another mobile app update. No notice or release notes to be found anywhere but the app notified me that you no longer have to long hold the button to lock, unlock, or start the vehicle.
Still no response from GM about why the pro trailering features have been removed or if there is any intention to address customer’s displeasure with the decision.
RDecker55
New Contributor
5 months ago
I just found this myself this week when I hooked up my trailer. The light test was one of the best features of the app.