low beam headlights failure

Most likely a bad connector somehwere. Here are some tests that I would do (a 12V test light will cost you very little or can even be improvised). Is there voltage at the headlight bulb's terminals? If there is you probably have a bad ground Is there voltage at the headlight end of the fuse? If there is voltage at the headlight end of the fuse the problem is in the wiring between the fuse and the headlight. Do you get the idea - trace the current path step by step starting at the fuse block ...

Try the switch.

Dave,

Usually, if the high beams work that means that the power is getting to the lights. On Toyotas, the control switches turns the ground on and off for the headlights. The headlights will always have positive power to them. I have a wiring diagram for a '95 Camry. There is a good chance that the same control approach is used for your Tacoma (but no guarantees). Everything I say from here on assumes that the Camry wiring controls is the same as the Tacoma wiring controls.

If you've got high beams, that means that the headlight relay and both left and right fuses are intact and working. The low beams have a continuous ground that is not switched through the light switch. All is pointing to a bad ground. The ground does not go through the headlight switch. Check for a broken or rusted electrical connection from the lights to the left front fender area.

Tell the usegroup how it turns out. Good luck. If you have any more questions, email me back and I'll try to respond.

Paul. Phoenix

Dave,

I had the opposite on my 94 (low beams would work but high's would not) ended up being the switch.

My guess is the headlight switch.

There is most likely a bad ground @the light, try to clip a wire to light, and to frame or engine. chaz