Biber/BibLaTeX \printbibliography causes "undefined control sequence" in the proceeding line

I had a similar issue. I pinpointed the problem to be in the .bib file. My advice is to carefully examine your .bib file for possible ambiguous syntax. In my case, the problematic syntax was:

...
title = {A 70~kW stationary fuel cell system},
...

The undefined control sequence issue was resolved, when this was changed to the following (i.e., the expression with the tilde was enclosed in the curly braces):

...
title = {A {70~kW} stationary fuel cell system},
...

A short comment (maybe someone will find it useful). In my case, the issue occurred after the matlab-prettifier package was loaded, which also loads the listings package. Until these packages were load, I had experienced no issues whatsoever.

The problem in the bibliography.bib file (https://gist.github.com/gfarrell/9892791) was an undefined control sequence after all: ADSABS inserts control sequences for journals like \aap.

Removing these and replacing them with the actual journal names fixes the problem.

(If anyone knows a package that defines all of these it would be quite helpful).