This goes back to the days when cars had generators and limited electrical power. And, pre 66 or so cars turned off the front parking lights when the headlights turned on.

Some cars use the front turn signal bulbs to create a DRL.

In Europe from what I recall, there is such a thing called city lights, these are essentially slightly brighter front parking lights.

GM was a big proponent of headlight DRL ( reduced output high beams ) , the problem here is the headlights wash out turn signals on a sunny day.

And while I'm at it, front turn signals behind a clear cover are useless and any angle off head on and even head on is dim. Sure, they pass the light output test, but in the real world, not having the lens light up makes them difficult to see.

I saw this thread on another forum and thought some here might find it interesting:

Any experience with flashing brake lights mod? - Triumph Forum: Triumph Rat Motorcycle Forums

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.

I went back and turned my adaptive lights off on the W164 after reading the other posts.

Apparently the experimental trial was not approved or extended to other vehicles.

Given the high volume of litigation and people looking for a loop hole it was not worth the chance of getting sued or getting a rear ended claim flipped back to being my responsibility.

I am going to research further and see what I can find. I am an MBCA member and I may try pursuing this over on their message boards.

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The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech