tacoma brakelight/tailight problem

02-23-2007, 07:21 AM
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:

02-23-2007, 11:00 AM
You have a shorted wire somewhere. Get a multimeter and a wire diagram and tear in.

02-23-2007, 12:01 PM
That is what I thought. I will find a diagram somewhere. Any suggestions?

02-24-2007, 03:37 AM
Factory Service Manual
Haynes Manual

03-02-2007, 08:12 AM
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

03-03-2007, 05:01 AM
Thanks for letting us know. I have heard of some other trucks with lighting problems due to trailer wiring.


03-03-2007, 09:32 AM
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.

Add your comment to this topic!