Installed Factory (Auer) LED DRL/Fogs without extra switch.

[q451990]

Please forgive me if this has already been mentioned, but I couldn't find it in a search.

One of the minor things that annoyed me about the South East Toyota Distributors (Auer) dual fog/DRL kit was that there's an extra DRL switch that has to be installed on the dash. Well, at least it's extra if you have the automatic headlamp feature with the bottom setting of "DRL Off." Anyhow, I installed mine yesterday, and modified things a little, so that the DRL's behave mostly like factory ones (no ebrake integration, but otherwise the same), turning off if the stalk switch is set to "DRL Off" and on at other times.

From some other posts, I figured out that the factory stalk switch supplies ground to the white wire in it's connector any time the switch is set to anything other than "DRL Off" position. Using this ground, I placed a second relay in place of the supplied DRL switch, to control the relay that comes with the kit. I then bent pin 2 on the under hood factory DRL relay, to defeat the OEM DRLs.

Hopefully the modified block diagram from the kit explains this better than I probably have in this post.

My installation is the one named "Dual DRL Diagram, as installed" and for reference, the diagram that came with the kit showing the switch is labeled "Block Diagram"

 

[q451990]

And to explain something, I know that I could have possibly just supplied ground from the stalk switch to pin C5/4(86) on the relay that came with the kit, and supplied 12V to pin C5/3(85) and accomplished the same thing - but the harness to that connector has a lot of diodes in it, and Auer's marketing for this kit brags on how well they isolated the kit with diodes, so I thought my relay setup woud be the safer option without inadvertently bypassing some of their protections.

 

[IslandJim]

Very interesting, thanks for your post. The dual DRL switches does seem redundant.

Does this bypass the high beam DRL's making the Auer fog lamps the only DRL?

edit; Think you did say bending the #2 pin on the oem relay defeats the oem DRL's.

 

[q451990]

Yep... pin 2 had to be disabled on the relay to defeat the OEM DRLs. I tried kapton tape to cover the pin, as suggested in another thread, but couldn't get it to work.

I also spent a good bit of time trying to figure out what kind of voltage that pin was getting, in hopes of triggering the Auer kit with it, but got nothing usable. Probably LAN pulses, something like 57mV when the DRLs were on, and 2mV when off.

I'm going to have to adjust the fogs tonight. When I went on a test drive last night (more like 2:00 am), I was seeing my neighbor's roofs, and squirrels in the trees really well.

 

[Hydguy]

Very interesting, thanks for your post. The dual DRL switches does seem redundant.

Does this bypass the high beam DRL's making the Auer fog lamps the only DRL?

edit; Think you did say bending the #2 pin on the oem relay defeats the oem DRL's.

The switch allows you to turn the outer LED DRLs on when all the other lights are off, which allows the LEDs to run on full brightness.
You can also turn them off by the switch.
when they are turned on, and you switch you headlights on, the LEDs run at a lower brightness.
The switch doesn't affect the fog light function, as that is controlled by the fog light setting on the stalk.