How do you operate a Gps system in a 2005 GMC Yukon Denali

Check the manual and follow instructions.

You should stop by your local gmc dealers service dept.The shop foreman will give you a copy from all data that will show you everything you need to know about the GPS system use and operation.Best of luck.

In Worst case, go to a GMC used car dealer & have the salesman show u the 2005 GMC Yukon Denali & how to operate the GPS in it.
You r not likely going to have any new car salesman help u if u just go to a dealer & ask about ur 3 year old GMC on how to use ur GPS, they r more incline to try to sell u a new GMC than to educate u on a older GMC GPS unit. They probably do not know either.

Hate to say it, but if u bought ur GMC new, than go back to ur original dealer, if u bought it used, u should ask the guy that sold it to you.

Do u know who was the GPS manufacturer? Denso, Pioneer? If u know who made the GPS unit for ur GMC, u maybe able to get some help from the GPS manufacturer.

Here is a link to some aftermarket GPS manuals that may help some people
http://retrevo.com/samples/GPS-manuals.html?cmpid=Manuals_GPS&s_kwcid=gps%20manual|1521418551&gclid=CJyf1arBrJQCFScuagodAl5KuA

If u can find someone near u that have a 2005 GMC Denali for sale that have a GPS in it, it maybe worth it to contact them & ask them how to use the GPS system, it will take more than a few minutes if u really wish to learn how to use ur GPS system to it is full capability.

Good Luck