I just bought LED turn signal bulbs/1156's for my 91 toyota pickup, and they will work in the rear of truck but not in the front. Can you tell me what I am doing wrong?

I would try measuring for 12 volts at the socket while the turn signal is on.

There could be additional fuses under the hood in the distribution box

You would check the socket with a test light or meter to see if you have power and ground. If no power, the turn signal switch would be the next thing to check.

check all bulbs,inspect sockets for corrosion,rust ,or sighns of overload.follow wires and check connectors if all good ,replace the flasher ,,if that doesnt fix it ,the blinker switch in the steering coulmn would be next

take the cover, twist it the bulb and replaced.

Check the front lights. Usually if i flashes fast it indicate a bulb is out on that side.

check the front right bulb

Hello terencewelch...the lens covers on these older models trucks seldom come off without damge. They are sealed with a gasket and compound to make them weather proof. You should be able to replace the bulb from the rear of the assembly. If you cant get to it from the back, slide the entire turn signal assembly out to access. Here is picture of the assembly for reference.
Good luck...i hope this helps and will fixya up.

This typically occurs when a turn signal bulb is out on the side blinking fast.