1999 tacoma prerunner 2 wd-- When brake pedal is pushed,dash lights come on and brake lights work. When lights are turned on, both filaments in brake/tailight bulbs come on. Pressing brake pedal has no effect when lights are on except a dimming of the dash lights. :banghead:

You have a shorted wire somewhere. Get a multimeter and a wire diagram and tear in.

That is what I thought. I will find a diagram somewhere. Any suggestions?

Factory Service Manual
Haynes Manual

Thanks for all the input. The problem was an incorrectly wired 4 -wire trailer plug placed there by the previous owner. It was WAY back under the rear bumper. Disconneced and all rear lights/brake lights are working properly. Power to brake lights were feeding dash/running lights during the day & at night, the tail lights were feeding power to the brake lights !:screwy:

Will wire now with the proper kit.:p
Thanks

Thanks for letting us know. I have heard of some other trucks with lighting problems due to trailer wiring.

Clifton

Many people probably do not note that the signal bulb is a separate circuit on the Tacoma. Most trailers use the brake filament of the dual filament bulb for turn signal.