ThreeCW

KMB - it has been a few years ... were you able to resolve your DRL issue?

I have a 2008 RX350 where the DRL are not working. I also have one burned out high beam, so perhaps that could be disabling the other DRL. Thanks for explaining in your first post that the DRL's run using the high beams at 6 volts ... good to know !!

KMB

Yes, I found within Techstream that the DRL feature had been disabled (presumably by the original owner), so I re-enabled it. Everything has been fine since then.

I am using allegedly "flicker-free" LEDs for the DRL/High-beam lights, and there is a very slight flicker when running them as DRL's @ 6V. I don't feel it's a problem and it might have the side-effect of slightly increasing noticeability. (I certainly prefer it to the anemic yellow DRLs on RX's that are still running incandescent bulbs.)

Felix

The drl not working & the passenger side highbeam out= someone removed the #21 relay......which I did yrs ago, as I drive w/ the headlights on.....I found many ppl running w/ drl's & not using their headlights, dusk, rainy weather....

ThreeCW

I got my replacement high beam bulbs from Amazon today for my 2008 RX350 ... Phillips Vision bulbs (30% more vision) in the 9005 PRB2 65 watt specification. The right high beam had burned out and neither of the DRL's were working.

I installed the 2 new high beam bulbs and now the DRL are working again (i.e. DRL use the high beam bulbs but at 6 volts instead of 12 volts as explained by KMB in his original post).

I may not get to evaluate the +30% Phillips Vision bulbs as I am in the process for selling the 2008 RX350 and we are now driving a new to us 2014 RX450H.

Thank you to KMB for your guidance on the Lexus DRL system

Felix

Good luck selling your rx. Should go pretty quick.