# Resistor makes high beam bulbs dim for Daytime Running Lights? **URL:** \ **Category:** General Discussion\ **Created:** [February 3, 2015, 9:49pm UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922 "2015-02-03T21:49:01Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Robert-Gift](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/robert-gift/32/356_2.png) [@Robert-Gift](https://community.cartalk.com/u/Robert-Gift)\ **Post date:** [February 3, 2015, 9:49pm UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/1 "2015-02-03T21:49:01Z")
How do they make the highbeams dim for Daytime Running Lights? Thank you. ---
**Author:** ![Triedaq](https://avatars.discourse-cdn.com/v4/letter/t/65b543/32.png) [@Triedaq](https://community.cartalk.com/u/Triedaq)\ **Post date:** [February 3, 2015, 11:04pm UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/2 "2015-02-03T23:04:32Z")
I believe that the high beam filaments are connected in series for the Daytime Running Lights. This effectively halves the voltage each filament receives. ---
**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\ **Post date:** [February 3, 2015, 11:23pm UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/3 "2015-02-03T23:23:47Z")
There are a number of different schemes being used. Perhaps if you told us who “they” are, someone can be more specific. It might even be helpful to know **why** you want to know… ---
**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\ **Post date:** [February 3, 2015, 11:47pm UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/4 "2015-02-03T23:47:10Z")
@Tridaq is right, the lights are wired in series rather than parallel to lessen the light. The wiring goes to parallel when the lights are turned on. The less light, I think, is so you don’t run around at night with DRLs ON and no tail lights, but that doesn’t seem to work very well. ---
**Author:** ![PvtPublic](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/pvtpublic/32/13089_2.png) [@PvtPublic](https://community.cartalk.com/u/PvtPublic)\ **Post date:** [February 4, 2015, 1:00am UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/5 "2015-02-04T01:00:30Z")
On my 99 Camry it was a resistor on the firewall. On my 02 Camry, no clue. ---
**Author:** ![insightful](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/insightful/32/2732_2.png) [@insightful](https://community.cartalk.com/u/insightful)\ **Post date:** [February 4, 2015, 2:46am UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/6 "2015-02-04T02:46:09Z")
On my Insight, the control unit rapidly turns the high beams on and off to achieve reduced brightness. ---
**Author:** ![ken\_green](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/ken_green/32/816_2.png) [@ken\_green](https://community.cartalk.com/u/ken_green)\ **Post date:** [February 4, 2015, 5:29am UTC](https://community.cartalk.com/t/resistor-makes-high-beam-bulbs-dim-for-daytime-running-lights/88922/7 "2015-02-04T05:29:48Z")
AND…I can’t stand that the fog lights turn OFF when the high beam is turned on…that’s pretty stupid. ( I had aftermarket fogs on my 92 and could see the world ! )