U180F Code intermittent - 2012 Tahoe Hybrid

[Robbie The Tiger]

First off let me say that I didn't post this in the hybrid section because I don't believe it is hybrid specific.

2012 Tahoe, 160,000 miles, otherwise in great shape. I have a very annoying issue. When it is cold outside (<37 deg F) I will occasionally get a warning bell/ding and the display shows SERVICE BRAKE SYSTEM, SERVICE STABILITRAK, and SERVICE TRACTION CONTROL. There are NO driveability issues when it happens, and it usually clears in a few seconds, only leaving the little skidding car light lit. The displays themselves clear. When I restart the vehicle everything is cleared. Again, this only happens in cold weather, and no other issues are apparent.

I was able to catch it happening one time, when I borrowed a friend's code reader (his was much better than my bluetooth Amazon special with Torque app but still not the GM Tech reader). The code I was able to pull was the U180F which is a data communication loss, data circuit B.

I am not sure how to troubleshoot at this point. I haven't been able to find a network wiring diagram that maybe would show the routing of this data circuit, with wire colors maybe(?) so I could check the wiring at the individual modules and see if there is an intermittent or suspect connection. This all started happening probably about around 120,000 miles. Kind of seems to be getting worse, happened (4) times this morning on the way to work. Soon though, it will be warm enough and I won't have the issue until next fall/winter.

If anyone has a wiring diagram that would help me out in this regard, or can point me in the right direction for one; or if you have had a similar issue or any suggestions at all, it would be appreciated. I would LOVE to fix without dealer involvement (story for another time) but I imagine that is everyone's goal on here . Thanks

 

[j91z28d1]

I'll look up a diagram when I get a chance.


I haven't looked up the code but do you have the rear air ride shocks? from other posts it's almost always the module under the rear where spare tire would be that has wiring issues.

 

[Robbie The Tiger]

I'll look up a diagram when I get a chance.


I haven't looked up the code but do you have the rear air ride shocks? from other posts it's almost always the module under the rear where spare tire would be that has wiring issues.

Thanks! That would be great. I do NOT have the air ride shocks but that module was going to be my first check. It just seems it would be the most exposed and least protected. It would be nice to know which wires/pins may be the problem. I appreciate your input.

 

[Robbie The Tiger]

Thanks! That would be great. I do NOT have the air ride shocks but that module (at least the one in the back, near the driver's side frame, think it may be the fuel pump module?)was going to be my first check. It just seems it would be the most exposed and least protected. It would be nice to know which wires/pins may be the problem. I appreciate your input.

 

[j91z28d1]

so the dtc doesn't seem very helpful but heres what I got.

you might need to invest in a scanner that can show the can network stuff. like in this video, I'd say a clone tech 2 is the most useful for these, but I haven't see anyway to show can network activity like his can, and that seems very useful for this stuff

I have seen a few threads on other boards about the serial Gateway module replacement but it has its own code and of course they say gm doesn't make it anymore. but they also say it's used on a few different cars but has to be programmed to work in our trucks. but we won't go down they ribbit hole unless needed haha.

 

[Robbie The Tiger]

Thank you so much! The video is definitely similar to what I have going on but thankfully I don't have the 'no start' issue. Maybe if the condition persisted longer I would. I wish I had the scan tools he had, a little out of my price range.

Because of the temperature aspect I would suspect a connection issue, shrinking connector or pins but I guess it could be the module itself. Even more hesitant to take it to a dealer now since it seems like I would be handing them a blank check.

I'll use your provided diagrams and see if I can get creative to track it down. The intermittent aspect (and temp) really makes it difficult though.

I appreciate you help! The diagrams are going to be hugely helpful as well as the vid.

Rob

 

[j91z28d1]

good luck with it.

random issues are the worst thing to find.

 

[petethepug]

B data cable. Isn’t that the can/bus line? Loss of communication could indicate comprised battery cables. They like to rot from the inside out. Cold weather observation is key.

You’ve got quick connectors on your 12v. There’s some NOS cables on eBay that are about 3-$4h off dealer, if they’re not already discontinued.