2021 Yukon - No Key Found - No Start Condition

[fondupot]

Hi all, new to me Yukon acting up...63,143 miles.

I had the transmission serviced this morning at my local transmission shop, basic fluid and filter job. I also had them reset the brake life monitor because the dealer I purchased from replaced the brakes but didn't reset the monitor. After picking up the truck and driving home I made one stop at the UPS store to drop off a package, it was a short drive may be 10-12 minutes.

When I got back in the truck, the cluster says NO KEY FOUND. And then to put the key in the cup holder to start vehicle. I tried that, nothing working. The fob still worked to lock/unlock the doors, but it wouldn't start the truck.

Got an Uber to take me home to get the other key fob and bring me back. Got back, the truck fired up like no problem. Drove home (about 10 minute drive).

When I went to shut the truck down I got two messages on the cluster.
1. Key Missing One Restart Allowed
2. Vehicle Will Shut Down After 1 min

Now the truck is dead again, it wont start with either FOB.

Both key fobs got fresh batteries just a few days ago, because one was saying key fob low battery when we bought the truck.

I popped the hood and disconnected the negative battery cable and I've been letting it sit for a while. I haven't tried starting it again yet.

Wanted to post here and get some input.

Much appreciated.

 

[fondupot]

Here are the two messages I got on shut down.

 

[Cjamaco79]

Hi all, new to me Yukon acting up...63,143 miles.

I had the transmission serviced this morning at my local transmission shop, basic fluid and filter job. I also had them reset the brake life monitor because the dealer I purchased from replaced the brakes but didn't reset the monitor. After picking up the truck and driving home I made one stop at the UPS store to drop off a package, it was a short drive may be 10-12 minutes.

When I got back in the truck, the cluster says NO KEY FOUND. And then to put the key in the cup holder to start vehicle. I tried that, nothing working. The fob still worked to lock/unlock the doors, but it wouldn't start the truck.

Got an Uber to take me home to get the other key fob and bring me back. Got back, the truck fired up like no problem. Drove home (about 10 minute drive).

When I went to shut the truck down I got two messages on the cluster.
1. Key Missing One Restart Allowed
2. Vehicle Will Shut Down After 1 min

Now the truck is dead again, it wont start with either FOB.

Both key fobs got fresh batteries just a few days ago, because one was saying key fob low battery when we bought the truck.

I popped the hood and disconnected the negative battery cable and I've been letting it sit for a while. I haven't tried starting it again yet.

Wanted to post here and get some input.

Much appreciated.

Yes I see. It. should be fine after you reconnect the car battery.

 

[fondupot]

@Cjamaco79 any thoughts to what might have caused this?

Did the transmission shop resetting the brake life monitor maybe trip up the computer or something?

 

[Cjamaco79]

@Cjamaco79 any thoughts to what might have caused this?

Did the transmission shop resetting the brake life monitor maybe trip up the computer or something?

Maybe the shop disconnected a few wires with out removing the negative terminal from the battery and the computer went crazy

 

[fondupot]

I’ve had two trips now without issue. I’m gonna chalk it up to being a glitch. Hopefully that’s all.

 

[Doubeleive]

I’ve had two trips now without issue. I’m gonna chalk it up to being a glitch. Hopefully that’s all.

just throw wrench in the glove box for the battery for "next time"
mine has a opposite issue, if you disconnect the battery it won't start, so you have to disconnect it a 2nd time. OR use a scanner to clear the security module error
seems to be some kind of module handshake issue when power is interrupted.