http://www.legacytuning.com/DRL/DRLdisable.htm
Here's another way
This is only for 99 Camry’s, 2000 Camry’s are a little different. It does however work on 99,00 Solara
To turn off your DRL's -- you'll want to unplug the DRL resistor pack in the engine bay, located in the corner near the passenger
side firewall.
If you look in that corner about a foot down or so, there's a metal box roughly the size of a pack of gum, maybe a little bigger.
It sits on a metal bracket and is attached at a 45 degree angle to the corner. It'll probably have some kind of "don't touch" label on it since it gets pretty hot under use.
If you know where your engine diagnostics connector is, it's roughly in the same corner except closer to the firewall and further down. Unsnap the two connectors and there it goes.
The sensor on the dash controls the "auto low-beam" feature (twilight sentinel). To unplug the dash sensor, pop off the top with a small screwdriver, unplug the sensor, and put the cover back on.
You should use a zip tie or a piece of string to tie the sensor to the cap so it won't fall into the dash. That way you can re-enable it in the future if you choose to do so
DRL disable
It worked fine until I fixed it! 
Linear Mode
