Left and right signals don't work. Where should I start looking?

If I remember right, there are separate circuits for the left and right sides in the power distribution module under the hood. I would check for hot spots and corrosion at the back side of the PDM.

Look for a bad ground on the circuits. If you dont have a good ground the circuit will back feed looking for a ground. Try it.

it's the grounds if they're both flashing fast it's definitely grounds take a test light and see if its got power goes through the test light grounded to the frame and if the light comes on then it's definitely your grounds

first of all check and confirm whether in the fuse box separates the left from right side and see for blown fuse. or check for any disconnection on the rear light

Is it a 4.0 v-6 engine? The sending unit is to the left of the thermostat housing.The one to the right(as you look at engine from the front)is the ECT that sends signal to computer.So replace the one to the left. don-ohio (:^)

try pushing, pulling, tugging on hazard switch button when turn signal is on, left or right, if they start blinking, the turn signal switch is bad.

you may have a blown fuse. that would be where i would look first.

Replace the turn signal switch. All of these lights run threw it.

Look inside under the steering wheel to the left,remove the lower steering column cover and knee pad panel to see junction box. The each fuse and relay will be marked for the right turn signal and the left turn signal. Look for a blown fuse on the left side. If not then the relay will be at fault. Before you start look to see if either turn signal lights are working on the left side. If the front is working and the rear is not then it will ba a short in the wiring to the rear causing the problem. Hope this will help you.

sounds like a bad turn signal switch, wiggle it , just a little bit,... see if some of the lights start to work. do your turn lights work correctly??