Electronic issues with no warning lights

[oregon2026]

So I’m new here and looking for some help. I have a 2020 Chevy Tahoe with 87k for miles. For the last 2 months my vehicle shuts down with now warning light, my steering goes stiff can’t turn vehicle without some muscle,dash lights go dim, head lights go dim vehicle stops moving. Last month Tahoe wouldn’t start after completely stalling. No lights no nothing, this time check engine light came on and gave me a code of U0101 (2/2) permanent Lost Communication with TCM. This code and light only came on one time. This happens intermittently and rain or shine. Dealership tells me they don’t know. Wondering if anyone else has had this issue or has any advise.

 

[the 18th letter]

So I’m new here and looking for some help. I have a 2020 Chevy Tahoe with 87k for miles. For the last 2 months my vehicle shuts down with now warning light, my steering goes stiff can’t turn vehicle without some muscle,dash lights go dim, head lights go dim vehicle stops moving. Last month Tahoe wouldn’t start after completely stalling. No lights no nothing, this time check engine light came on and gave me a code of U0101 (2/2) permanent Lost Communication with TCM. This code and light only came on one time. This happens intermittently and rain or shine. Dealership tells me they don’t know. Wondering if anyone else has had this issue or has any advise.

What’s the status of the battery? New or original

 

[RAMurphy]

Welcome to this great forum.

 

[preinternet]

So I’m new here and looking for some help. I have a 2020 Chevy Tahoe with 87k for miles. For the last 2 months my vehicle shuts down with now warning light, my steering goes stiff can’t turn vehicle without some muscle,dash lights go dim, head lights go dim vehicle stops moving. Last month Tahoe wouldn’t start after completely stalling. No lights no nothing, this time check engine light came on and gave me a code of U0101 (2/2) permanent Lost Communication with TCM. This code and light only came on one time. This happens intermittently and rain or shine. Dealership tells me they don’t know. Wondering if anyone else has had this issue or has any advise.

Sounds like Cam or crank sensor find out what your coding first thought before you spend for the wrong part

 

[rustyj671]

So I’m new here and looking for some help. I have a 2020 Chevy Tahoe with 87k for miles. For the last 2 months my vehicle shuts down with now warning light, my steering goes stiff can’t turn vehicle without some muscle,dash lights go dim, head lights go dim vehicle stops moving. Last month Tahoe wouldn’t start after completely stalling. No lights no nothing, this time check engine light came on and gave me a code of U0101 (2/2) permanent Lost Communication with TCM. This code and light only came on one time. This happens intermittently and rain or shine. Dealership tells me they don’t know. Wondering if anyone else has had this issue or has any advise.

Did you ever find a fix for this?
My 2019 with 78k on it is doing something similiar. I've noticed that the headlights will dim when I activate the brake lights as well. If I'm stopped and turn the steering wheel, sometimes it will be harder than normal to turn and the headlights will dim. Two days ago, I went to reverse into my parking spot at work and it died completely as if I shut it off. No radio, no lights, no engine, just nothing. I'm leaning toward it possiibly being the alternator (voltage regulator actually) but all of my searches keep coming with ground issues. No CEL either.

 

[rustyj671]

Did you ever find a fix for this?
My 2019 with 78k on it is doing something similiar. I've noticed that the headlights will dim when I activate the brake lights as well. If I'm stopped and turn the steering wheel, sometimes it will be harder than normal to turn and the headlights will dim. Two days ago, I went to reverse into my parking spot at work and it died completely as if I shut it off. No radio, no lights, no engine, just nothing. I'm leaning toward it possiibly being the alternator (voltage regulator actually) but all of my searches keep coming with ground issues. No CEL either.

I should also mention that the blind spot detection lights on the mirrors come on at random times. Not both at the same time though.

 

[Miami-Dade]

@rustyj671 The OP has not been here since since his first post on May 10.

 

[rustyj671]

@rustyj671 The OP has not been here since since his first post on May 10.

Well that's just disappointing.

 

[ReaperHWK]

I should also mention that the blind spot detection lights on the mirrors come on at random times. Not both at the same time though.

I had similar electrical gremlins. My issue was the side detection modules were faulty and corrupting the can bus. You may have a similar issue if your blind spot monitors aren’t working correctly. If I were you I’d disconnect both of those modules and see if the random errors go away.

 

[Foxguy1973]

Did you ever find a fix for this?
My 2019 with 78k on it is doing something similiar. I've noticed that the headlights will dim when I activate the brake lights as well. If I'm stopped and turn the steering wheel, sometimes it will be harder than normal to turn and the headlights will dim. Two days ago, I went to reverse into my parking spot at work and it died completely as if I shut it off. No radio, no lights, no engine, just nothing. I'm leaning toward it possiibly being the alternator (voltage regulator actually) but all of my searches keep coming with ground issues. No CEL either.

I have a 2015 and was having the exact same issues…hit the brakes during a turn and it would die, then start right back up. After some exhaustive research, I found where someone suggested replacing the pos battery cable due to corrosion buildup inside the cable. It’s the short, 6-inch cable going from the battery to the junction block. I replaced it three years ago and haven’t had the same issue happen since. Cheap fix, too. I still have some issues with my “adaptive cruise control unavailable” message popping up randomly, but otherwise it’s been a solid truck.

 

[rustyj671]

So I think I got mine resolved week before last. I was checking other ground connections and on a whim, thought I'd put a wrench on the battery terminals. The battery was brand new when I got the Tahoe 10 months ago, so I never gave it a second thought. However, it did look like the negative terminal wasn't fully seated on the post. Well, it didn't take much effort to loosen the bolt and I got the terminal down another 1/8-3/16. The positive side was about the same, so I took the negative off and started on the positive side. Welllllll.....it wasn't even tight! I pulled it off, cleaned up, added some dielectric grease and made sure the terminal was FULLY seated. I did the same for the negative side. It's been two weeks and NO ISSUES!