What's Wrong With Your Yukon/Tahoe Today? ...And How Long Has This Been Happening?

[ProfeZZor X]

In the last few months, my Yukon had a software update. Since then, little things have been happening like random chimes, random icon displays, and so on. But, it's not so much that it's been a major problem... Until now. Now I can't unlock my doors using the door handle button. I have to manually unlock it using the key fob. I'm wondering if it has to do with my key fob battery, and that it won't give off a signal to the vehicle if the battery is low. I could be wrong, but has this happened to anyone?

 

[WalleyeMikeIII]

iPhone autoconnect using Wireless CarPlay never works at startup, was a periodic occurance, but after iPhone update to iOS 17, its a sure thing, 95% of the time it will not autoconnect at startup.

Workaround is:
On Infotainment system:
-Hit Phone Icon
-Select Manage Phones
-Disconnect the iPhone
-Wait for the phone ot disconnect and until CarPlay icon appears in the phone icon on the screen
-Touch the icon, about 5s later, it connects.

 

[B-train]

On my 2008 Denali, I've had a rough idle on startup and lower brake pedal assist for a number of months now. Coupled with a bit lower than expected MPG. I figured I had a vacuum leak of some sort. Also, the fuel trims seemed to be off a little bit compared to what I've seen on this site from others - I attributed this to my running of E85 blends to find the sweet spot so didn't really think much on it.

Last night I decided to have some homemade wine and give the old girl a look-see. All vacuum lines looked good, intake bolts tight, etc. While poking around, I noticed map sensor wasn't tight in is hole. I removed it to find the ribbed o-ring all flattened out from 182k miles of use.

I fluffed up the ribs as best I could, then coated it with a healthy dose of grease and plopped it back in as a test. Fired up the truck and it idled as smooth as glass. Took a test drive and noticed smoother running, better braking, and fuel trims in the 0-1 range.

It was a shot in the dark, but seems to have helped. Time will tell on a couple more uses, but so far, so good. I will get a new GM sensor after the testing is done. It's amazing what affect a small vacuum leak can have.

 

[cmatthews77]

2021 Tahoe and the FM radio doesn’t work initially. The workaround is I have to hit the home button, audio, then go to AM radio and then back to FM radio and it’ll work. If you go to FM first it won’t play.

 

[KMeloney]

2021 Tahoe and the FM radio doesn’t work initially. The workaround is I have to hit the home button, audio, then go to AM radio and then back to FM radio and it’ll work. If you go to FM first it won’t play.

Is your iphone auto-connecting when you get in the truck? I've found that if it does, and your phone is trying to play audio/video on it (even if it's on a site that has a pop-up video ad trying to play), then you get kicked out of AM/FM (not sure about XM), and you have to then toggle between frequencies/bands and back to where you were. Annoying, yes, but...

Is that what's happening in your situation, or does it happen even when your iphone doesn't auto-connect/when Carplay is not connected?

 

[cmatthews77]

Is your iphone auto-connecting when you get in the truck? I've found that if it does, and your phone is trying to play audio/video on it (even if it's on a site that has a pop-up video ad trying to play), then you get kicked out of AM/FM (not sure about XM), and you have to then toggle between frequencies/bands and back to where you were. Annoying, yes, but...

Is that what's happening in your situation, or does it happen even when your iphone doesn't auto-connect/when Carplay is not connected?

Well I do sometimes get kicked off or disconnected from radio if the vehicle thinks I’m trying to play phone and I’m connected.

However, this is a different issue and happens whether I have my phone connected or not. The FM tuner won’t engage unless I first go to AM and then back to FM. It’s very annoying

 

[ProfeZZor X]

Took my Yukon to the Thousand Oaks GMC dealership Saturday morning for an oil change, and I guess it turned out being more serious than that. They found oil condensation on the pan, but no leaking. They replaced the gasket, and had to allow it to seal properly for a few days, which they were more than generous to provide me with a loaner. I also had some electrical issues which they promptly fixed, and also installed a brand new heated steering wheel that was due to me because of supply chain issues a few years ago. Because of the new steering wheel, I got a free wheel alignment, so that was a plus. They even went so far as to wash and fully detail my Yukon before I picked it up. Hell, it looked better than if I had washed and detailed it myself.

In all, I had a fantastic experience with them, and that's why I think it's worth the 100 mile drive to get there.

 

[Punteh]

Tonight on my way home from work my CEL came on after some shuttering. When I got home I connected my code reader and I got the code P0300 Random Misfire. My Yukon Denali has 6400km on it. Great. Are you not able to clear codes on these vehicles? Everytime I tried with my code reader it would lose connection with the vehicle. So the code is still there. Obviously being Friday night I won't be able to get into the dealer until at least Monday morning to look into it.

Any recommendations with this code for the weekend? Is it ok to drive or would that possibly make things worse?

 

[WalleyeMikeIII]

You could hit the onstar button and get the remote diagnosis will probably reveal more specific codes

 

[Punteh]

You could hit the onstar button and get the remote diagnosis will probably reveal more specific codes

Do you know if the CEL will prevent remote start from working? Today it's not starting with the remote or through the MyGMC app. It's starting fine using the start button in the vehicle