I'd start with the reset Nelson mentions, but the sequence for a diesel is.
- Power off
- PGM/RUN switch to PGM
- ENG, ##, SET
- AUX1, 8
- Power off
- PGM/RUN switch to RUN
If that doesn't do it, I'd be looking for a wiring flaw. When current is being drawn, it appears you're losing power to the markers.