With the engine running and the parking brake released, confirm whether the running lights operate only in gear rather than park. Also verify that both high and low beams work, since a burned-out headlight can disable the daytime running lights, and check the dashboard headlight indicator bulb. The headlight assembly can be moved aside by releasing its two retaining pins for inspection.
The owner of a 1998 Chevrolet Silverado reported that the running lights did not work even though the fuse was good, and asked whether to trace the wiring. One reply said daytime running lights use the low beams at reduced voltage with the engine running and parking brake off, and recommended checking for a burned-out headlight or dashboard indicator bulb. An expert added that a similar Silverado activates them only in gear, not park, and that the headlight can be accessed by pulling two pins. The owner planned to check both suggestions.
