[thomasthorpe]

Old thread now. But often a minimum load is needed for an LDO, particularly on older parts, to work correctly. Such that these are given in datasheets. This is continuously required so is effectively quiescent current. I think this is what the OP was trying to get at.

But failed capacitor reulting in instability seems much more likely.

[jonsen]

You are right that a small quiescent current is necessary for correct idle operation. But much of the discussion here is about the misconception that a certain ambient temperature is necessary for correct operation by design.

By the way it is in fact imaginable that aging has caused the quiescent current to become too small at low temperature.

There are several possible temperature dependent fault mechanisms caused by aging, so I wouldn't make a guess in this case.