High beam sensor on when low beams

Hi Tacoma forum,
Have on 03 extra cab that the blue high beam sensor was on when tried to turn on lights today. The lights do not turn only high beams when I turn them on. High beam senor stays on when lights are engaged, either high or low beams. Only high beams are working. I've read thru some threads and checked all the grounds. Nothing is loose. Sensor makes a clicking noice when turn on lights. Haven't replaced bulbs yet due to them both out same time and high senor on. Any additional help would be appreciated.

 

Stuck relay maybe... try and find headlamp relay, tap top with a screw driver handle?

Totally pulling that outta my ass, but its 1st thing id try besides checking bulbs wires, and fuses

 

It's possible both low beams are burned out. It's happened before. Try a new bulb. If it doesn't fix it, then save it as a spare. You'll use it eventually. Or you could check for voltage at the bulb connectors.

The circuit has two parts. One turns on the headlight relay which is the click you hear. The other allows the current to flow through either low or high beams.

On the other hand Toyota uses a weird circuit where the current for the high beam indicator goes through the low beam filaments when the high beams are on. If Toyota still used this type of circuit on the 03, this would imply at least one of your low beams bulbs is good, and the problem is in the headlight switch.

 

DrZ, 2002 Tacoma v6 4wd manual, no low beams, have high beams, high beam indicator is on with high beams of course, but when I go to low beams it stays on also, but no low beams. got new bulbs, still no lows, two fuses in fuse box under the hood good, also cleaned battery connections just in case, relay clicks from hi to low, does not have driving lights or any add ons. Truck has the TRD package I assume (it has the decals on the bed sides). Any suggestions? Hate to have to go to dealer if I can avoid it. Appreciate any help from you or anyone. Thanks

 

That is a fulty high/low switch not contacting in low beam position. This is my bet. The whole current from two bulbs (that is around 8A) goes through this contact. It is probably burned and not contacting anymore.
Based on diagram this is most likely problem.