daytime running lights, how do they work?
With the knob for headlamp control in position the daytime running lights (Daytime Running Lights – DRL) are activated automatically when the car is driven in daylight. A light sensor on the top of the instrument panel changes from daytime running lights to dipped beam at twilight or when daylight becomes too weak. Switching to dipped beam also takes place when the rear fog lamps are activated.
On cars with halogen headlamps the daytime running light lamps are switched off when main or dipped beam is activated.
MVS Forum Member cec asks:
Does anyone know how to disable the daytime running lights in a 2005 XC90 V8 with HID headlights. The dealer tried and was able to disable the rear DRLs but not the front daytime running lights. Dealer said that up to 2004 models DRLs could be disabled but after 2005 this is no longer possible.
MVS Forum Member hjself replied:
I have been told by Volvo service personnel that the daytime running lights cannot be disabled BUT you can control which lights come on ( I had a 2004 XC90 with BiXenon Headlamps). You can do that with the headlight selector switch. If the switch is placed in the upward ( on ) position, the BiXenons will come on during all driving conditions. If the headlight selector switch is placed in the full left ( off/automatic ) position, the daytime running lights will come on but it willa be the halogen lamps that illuminate during daytime running rather than the BiXenons. When the ambient light is below the threshold, the BiXenons will come on with the switch left in this position. However, you cannot engage the Hi Beam position on the BiXenons with that setting of the switch. If the headlight selector switch is turned to the up ( on ) position, then the BiXenons will be on and the Hi Beam selection can be made. The trick is to remember that when driving during daylight hours, the headlight selector switch should be in the full left ( off/automatic ) position and in the up ( on ) position during nighttime driving. I hope this helps
MVS Forum Member MadeInJapan added:
On ’04 V70’s you can have the daytime running lights illuminated. It does require a software download. Ask your dealer and see what they say.