I have a 2017 Kenworth t 660 and have no LED turn signal on front left and front right side but I do have them on the side of the hood and on the rear of the truck we replaced the wire harness and all the ohm out we even tried a new head light assembly and still have no turn sit in the front
Make sure that light has good ground to steel frame rail. The hood is fiberglass and may not have a ground strap from the lights to the frame. Leds will not even come on and glow dim like a bulb will if the ground is weak.
Disconnect the connector to the headlight assembly/turn signal. Turn the turn signal on. Set a voltmeter to DC volts. Connect the negative lead (black) to a good ground. Then try the red lead in each of connector ends. See if any of the terminals has 12-13v.
Have you unplugged the harness ( Left & Right side ) under the radiator lately ? They have a way of loosing ground with the water getting in the pins. The pins also bend and don't go where they need to be.
We replaced the harness and ran power through each wire replaced both head light assembly replaced both hood harness ohm out each wire and they all homes out good so now we are thinking it might be the node but have no way of checking it or if it can be checked
Still need to check for voltage at the harness where it connects to the headlight to see if the t.s. is getting to that point. If not then check the other end that connects to that harness. "ran power through each wire" What was the result, did the t.s. light up? What is the "node" you refer to?
Check all the way from the node and we’re getting 12 v and replace all the harnesses and head lamp assembly and still nothing the node is like a relay panel under the sleeper mounted to the cross member and when they started putting all the def c