2004 YUKON XL DENALI, new throttle messed up delayed shift points

https://www.autozone.com/repairguides/Escalade-Suburban-Tahoe-Yukon-Denali-DenaliXL-YukonXL-1999-2005/Seats-2004/Driver-Seat-Schematics/_/P-0996b43f80370a19 https://www.autozone.com/repairguides/Escalade-Suburban-1500-2500-Tahoe-Yukon-Yukon-XL-1500-2500-2006-2007-Yukon-Denali-and-Yukon-Denali-XL-2005-2006/Power-Seats-2007/Driver-Seat-Schematics/_/P-0996b43f80cb1bbc https://www.tahoeyukonforum.com/threads/power-seat-wiring-help.63730

Do you have a check engine light
4L60E check fuses before working on your chevy transmission
https://www.youtube.com/watch?v=pbaj0dOG2vg

GMC Yukon Denali: he cant shift into park..shifter
https://www.justanswer.com/gm/3z762-gmc-yukon-denali-can-t-shift-park-shifter.html

I put my truck into drive or reverse n it will not move at all what is causeing this to happen
https://www.cargurus.com/Cars/Discussion-t14601_ds575443

Shift but won't go into gear just revs
https://www.transmissionrepaircostguide.com/topic/shift-but-wont-go-into-gear-just-revs/

I have had vehicles where the speed sensor, MAF, MAP and throttle body did not let them shift as they should but the vehicle did shift. I have put several links above. Just to make sure if you have check engine light find out the code. Make sure you check transmission fluid with engine on and in park, emergency brake on at normal operating temperature. ( May sound bad but I have had to tell people above 30 about this and they said it was the first they heard of it). I will say the thing which stands out to me is check shifter cable. Check fuses. I did see a link which suggested brakes locked up but I assume the truck is not even trying to move.

GMC Yukon (2003 - 2004) - fuse box diagram
https://www.autogenius.info/gmc-yukon-2003-2004-fuse-box-diagram/

Without any smyptoms how do you know it is overheating? Post a comment and let us know.

throttle position sensor is prob. bad. unfortunately this mean replacing the throttle body

I had the same problem in my Yukon Denali And after 4 throttle body's, replacing gas pedal, rewiring the grounds replacing sensors, took it to not one but two GMC dealerships who were useless they can't fix their own trucks they're not the brightest !!!! After thousands of dollars I found a mechanic very familiar with this issue you want the solution it will cost ya 500$ for me to tell ya!! Just kidding I know how frustrating this problem is okay here is the fix the problem is these electric throttle bodies are GARBAGE!!!!!!! Don't matter what u do or what u replace it will come back on unless u convert your electric throttle body to the old cable throttle the actual fix was 900$ but I spent thousands and thousands trying to fix it!!! Please save your money and tell ur mechanic u want to convert to the old cable throttle!!! Gmc is well aware of the problem but won't fix it for u cuz they're useless

there are 2 conditions that will trigger this SAFE MODE that the engine is running in. The first is transmission over temperature when the sensor in the transmission senses over-temp situation it reduces engine output to no more than 1500 rpm. The second is low oil level in the engine, which will also limit engine rpm to 1500. One of those sensors is bad or the wiring for one of them is damaged. This SAFE MODE is designed to protect the engine or transmission from further damage.

try keeping the gascap tight

Check all grounds, battery connections. Clean them up and tighen them. If this doens't work, inspect the throttle body for leaks.

I had the same problem with my 2003 denali and came to find out that it was the battery causing the problem. the battery with sufficient power will dictate the tps. if the battery is low or bad, it won't have enough juice to allow the tps to. work. get your battery checked.

There are 2 fuse panels in the Denali.
One is a panel on the drivers side, its on the dash but facing the door.

The ohter is under the dash and above the pedals, this one is much tougher to access.

Your Owner's Manual should tell you where the fuses are that you need to access.