If you unplug the DRL resistor behind the battery and try to work the headlamps; what happens? I unplugged my DRL resistor to just have a normal headlamp system because I was blowing bulbs every six months. (it's been a year and a half and I haven't blown a bulb since.) The system will continue to operate just like a 4Runner w/o DRL's with this unplugged. It may help you in diagnosing the problem to take that variable out of the system.
drl resistor behind the battery? the little black box on the fender? mine is unplugged but the black box is gone lol..bought the truck like this...im an idiot n never checked the lights before purchase. seller didnt notify me either oh well now its my problem
i got 8 months before my annual inspection so I gotta get it done lol