Daytime running lights on the ML
 

A question for those of you who have daytime running lights (those of you who have their's turned on, or live in Canada or Europe).

When is the daytime running lights are on, are they still on when the headlights are on, or do they turn off when the head lights are turned on?
Ben

DRL = Headlight/Taillight on MINUS interior lights(cluster/switch lights)

Andy Kuo

Ben:
I'll look around at work and see if I can get an answer. My impression is that the DRL's are only on with the headlights "off", turning on the headlights deactivate them. I also believe the DRL's are only the 2 bulbs in the headlights that used to be the foglight socket. The feature in the US is only available starting in 2002 (on an ML). Be aware we did try to activate them on a 2002 and had trouble with the AAM and ended up not being able to activate DRL, may be an isolated case though, the guy at MB said they are working on a fix. I don't believe the tail lights will come on with DRL's, not 100% sure on that. On GM cars with DRL, the tail lights don't come on. Also, on Canadian ML,s, and I believe all or at least MOST of their cars, setting the parking brake for some odd reason also deactivates the DRL's, I'm not sure if this is true with US versions or not.
Gilly

Gilly, thanks for checking
 

Gilly, thanks for checking

For all late model Canadian MB(1995 and on), DRL = Headlights/Corner lights/taillights ON, however, interior illuminations remain OFF if the headlight switch is left in OFF position. DRL comes on whenever the engine started, HOWEVER, when the gear is in P or N, headlights are off, only corner lights and taillights are on. Once shift into D(or any gear), headlights come on.

Andy Kuo

Hi:
I still intend on checking this out, I believe the best resource will be a 2002 owners manual. Just been swamped lately installing snow tires and other winterization stuff, plus a few big projects for the shop.
I wasn't working on the ML that the owner wanted the DRL's on, but I know there was a big problem, wouldn't work. I believe the fix was to download the version programming from an ML55 into this guys AAM, I am unsure what the exact model was that was being worked on, must have been either a 320 or a 500. But I can't remember if the downloading from a ML55 was to just get everything working normally again, or if it actually got the DRL's to come on.
In the US, the biggest proponent of DRL's is GM, whether all the DRL systems in the US all work the same I don't know, but I have a Buick and my wife has a Blazer, both with DRL's. On our vehicles, the DRL's come on when the car is started and that's all. I just checked my wifes Blazer, and yes, they turn off if the parking brake is set. On the Blazer, it seems like the DRL bulbs shut off when the headlights are turned on. The DRL's remain on when the parking lights are turned on, then you will have DRL's, front park lights and tailights, plus intrument illumination.
On my Buick, the DRL's are also the front turn signal, so they are amber colored, they remain on when the headlights are turned on. The Blazer DRL's are in the bottom section of the headlight, they do appear like a dim headlight, not bright white but I don't believe the bulb is tinted at all.
I don't believe any of the US cars DRL's are affected by gearshift position.
Hopefully I can get a clearer view of how the ML DRL's operate either by the owners manual or we finally get them operating on a 2002.
Gilly

Quote from 2002 owners manual
 

Daytime running lamp mode (Canada only)
Turn exterior lamp switch to position 0 (off position symbol)

When the engine is running the low beam headlamps are automatically switched on. In low ambient light conditions the parking lamps will also switch on.

When shifting from a driving position to position "N" or "P", the exterior lamps switches off (3 minutes delay).

For nighttime driving the exterior lamp switch should be turned to the "on" position or "AUTO" position to permit activation of the high beam headlamps.

Note:
The high beam flasher is always available.

++++++++++++++++++++++++++++++++++++++++++++++
I assume this is how the US models will work when activated, not 100% sure.
By "high beam flasher" I assume they mean the "flash to pass" feature. Also in the second part, by parking lamps I assume they mean the front marker bulbs and the tail lights. No mention is made of the instrument panel lights, I would assume they come on when the parking lights/tail lights come on, due to low ambient light conditions. In general I assume the cluster lights operate when the tail lights are on.
Gilly