2014 Yukon Denali running boards stopped working

Look in the owner's manual to see if you can find a relay for the running boards. If it has a relay it just might be bad.

I know this is an Old Post. But for anybody else who has encountered this issue, check your alternator I had a faulty alternator the battery was not holding a charge which causes the running boards to go into storage mode. 30 minutes later and a new alternator, I performed the procedure to initiate the running boards and they started right up. If both of your running boards fail at the same time it's unlikely to be a mechanical issue. Steps should be one check the fuse 2 try the initiation sequence you can find that just by Googling it and then three check the power that's going to those running boards in this scenario mine was an alternator issue and the battery was never fully charged enough to run the boards. Hope this helps

Fuse is good. How do I perform initiation sequence. Alternator is good ad well