The Tesla Coil / Energy Absorber equipment mechanics in Krastorio 2 don't work with electric locomotives in 0.2.9.
The mechanic requires that entities with equipment grids have is_military_target=true. It attempts to ensure this is the case in data-final-fixes by finding everything with an appropriate equipment grid and setting that flag.
However, Electric Trains only gain their equipment grids via the inheritance code in data-final-fixes, and as it lists K2 as an optional dependency it loads after K2's fixup attempt.
You could probably fix this with any one of these options:
- doing grid inheritance in 
data-updates instead of data-final-fixes (I tried this, it works) (K2 edits the vanilla locomotive to have a grid during data-updates) 
- copying 
is_military_target from the source prototype in the grid inheritance code 
- setting 
is_military_target=true on all of the vehicle prototypes 
- removing the explicit optional dependency on K2 (because this mod would otherwise be earlier in the load order)