The Rover-Landers of BC

Same thing has happened to me twice in recent months.

Two vehicles, 1994 Range Rover and 1991 Defender 110, both 300Tdi but other than that could not be more different, except that they were both modified for daytime running lights when imported to BC.

Problems is this: One headlight dip beam goes, then the other goes within 30 seconds of the first. The main beam remains good in both cases. On the rangie they are/were sealed beam GE nighthawk, on the defender they are stock halogen bulb units.

Daytime running conversion was done by different shops, so no coincidence there. I've replaced the rangie lights already and will do the 110 tomorrow to make sure it's the bulbs.

BTW - fuses are all good on both trucks (four fuses all together).

Any ideas what the chuff is happening?

Thanks, David

DRL uses Main beam on reduced output. The only thing I think could put the low beam element out would be a voltage spike. But I don't know how you would get one. You need to confirm it is an element burned out in the bulb and not something to do with the relay.