I have done many a PDI during my time at Renault. What we did should apply to ALL makes and models.
Vehicle is driven onto the ramp. Sat in driving seat with checklist. Then basically you go through the whole vehicle to make sure everything works, from front to rear. Does everything work as it should? If not, rectify it. The underside is also inspected. The fluid levels are then checked along with the tyre pressures before the vehicle has a test drive to make sure there are no noises and to align the steering wheel. Once I am satisfied that the vehicle is as it should be, I will then release it for the valeters to do their bit, before it has handed to the customer.
You name it, it was checked and tested. I used to enjoy doing the PDIs. I never had a Renault returned with something that wasn't right after I had carried out the PDI.
I'm sorry I can't be more specific, as it would take me an age to list everything on the vehicle that is part of the PDI. Nothing is supposed to be missed.