Operators, the excavator’s blackout (BO) drive light is mounted to a moveable drive light assembly that can be mounted on the loader bucket for Department of Transportation (DOT) approved on-road travel or to the vehicle’s cab for all other uses. However, the BO drive light portion of the assembly functions
only when the assembly is mounted to the loader bucket and connected to the loader bucket harness.
Here’s the catch: There’s no mention in the PMCS section of TM 5-2420-232-10 (Sep 10, w/Ch1 Sep 12) that tells you the vehicle’s BO drive light works only when it’s installed and connected to the vehicle’s loader bucket harness. As a result, during PMCS, the operator might waste time trying to fault-isolate a BO drive light that isn’t working. Knowing where it’ll work and where it won’t will help you avoid wasted time.
Keep this pointer in mind until the -10 TM is updated.