What has spooked me more than once is when everything was off and I was not on shore power, while removing the coach batt to add water, I touched one of the cables (the ground, I think it was) to the chassis frame and got sparks. If memory serves right, it happened again even after I replaced the EM solenoid.
I may be mis remembering some of this now - I kinda threw my hands up after a frustrating episode of vague assumptions all around. Something makes me think that elec step is wired wrong by TL, but it all seems to work generally right, and I am very careful with the coach batt cables nowadays.