My 2002 GMC yukon XL will not pass emission inspection due to OBD not giving a reading out the computer. The technician suggested I take it in for service and check all fuses. I check all the fuse and did not see any fuse blown or related to the OBD. Can anyone help?

Test all under dash and under hood fuses with a test light or multimeter. Here's how to do it properly:

https://www.askmehelpdesk.com/cars-t...tml#post252145

What he's saying is rediness monitors in the vehicles ECM have to be 'set' to perform an emissions inspection. At least 3 of those monitors on a 2k model here in NC.
If they're reseting, then I'd be checking to see if battery voltage is dropping or computer grounds are at fault. Something is being disconnected when going through a key cycle.
It's possible this lies in the ECM itself.