Is DRL consume extra fuel?

[Danny]

Just wondering if DRL (Daytime Running Lights) consume extra fuel or not? Somebody was arguing on this point and I also got curious to know the truth, if anyone knows here.

[gautam]

I doubt very much if there is a way to measure the extra fuel used by daytime running lights. These lights are Light Emiting Diodes, and their power consumption is typically measured in milli-amps, so depending on the model, the total power consumption on a set of daytime lights might be significantly less than one amp.

Any decent audio system uses way more power than that, so you might actually be saving fuel if you don't use your radio, but I would not worry about daytime running lights. They use so little power that I don't think the electrical system even notices them, in a manner of speaking.

[Saleem]

Hi Danny

I noticed that in small Japaneses and Korean cars that each and every tiny electrical load affects the engine ideal speed while AC not running starting from dim lights to single power window opening or closing even courtesy light for door opening while in larger size with larger battery 70 AMPS and up you can't feel that so I guess that larger batteries will not consume like small batteries.

simply extra electrical load would make generator heavier and would slow down ideal speed so engine ECU calibrate throttle angle and ignition and injectors to elevate engine speed to the factory specs RPM. while in larger battery case the generators just compensate the battery drained AMPS so it's not a permanent load.

DRL looks nice if it is carefully designed enjoy it!   

[Derick]

As explained above in short:

• Theoretically yes it impact fuel mileage very very marginally.
• Practically DRL doesn't impact fuel mileage, as it's hard to notice 100 ml extra consumption in 100 Liter of fuel.

I agree with Saleem, that it looks nice to drive with DRL on, and that's why it has been designed so beautifully to compliment the car looks and appeal. For 10 fils extra fuel on 100 AED tank fill-up you won't or shouldn't stop the use of DRL. My two cents.