2005 Volkswagon Passat Wagon not wanting to crank

My daughter drives a 2005 Passat station wagon, has a small child and one on the way. She has had intermittent problems with
the car just not wanting to crank. After sitting 15-20 minutes it will crank. But the wait and not knowing if it will crank is taxing me and her.
especially since she has another one on the way. She has taken it to a reputable mechanic. They kept it for 3 days, cranking it on and off without
a problem, and told her they couldn’t find anything. Anyone had this problem before? Know of any solutions? Help!

What exactly happens when it “didn’t want to crank”?

starter runs but engine does not fire up?
clicking noise only?
nothing, and dash dark?
nothing, and dash lights up normally?

b

Have Your Daughter Observe The Instrument Panel On This Volkswagen

Automatic? Have Her try moving the gear selector and firmly resetting it in “Park” the nest time it acts up.

Also, when it won’t start, have her turn the key to “On” for half a minute and then try the starter.

CSA

In A Volkswagen Technical Service Bulletin Pertaining To Intermittent No Starting, This Is Sometimes Caused By “Immobilizer Active Intermittently” .

A dash message “Immobilizer Active” illuminates (a vehicle theft deterrent). Volkswagen says the problem can be caused by having other transponders (fobs) or keys on the car’s key ring.

Did the mechanic find any diagnostic trouble codes? A PO513 indicates “key implausible signal”.
Make sure nothing else is on the key ring for this car and see if that helps.

I wonder if keys were removed from the key ring when she took the car to the reputable mechanic and fixed the problem temporarily without knowing it?

CSA