Ford123

I put all my lights LED third brake light lense brake lights (just put the bulbs in the tail lights) and a new relay now I have no cruise control is that because of the new relay or is it something else I tried looking up the problem but found nothing

Buck

This is common when replacing the 3rd brake light with an LED one on these trucks. Sometimes it happens sometimes it doesn't (quality of the light?) I was a one of the lucky ones that didn't have this issue. You will need to take the 3rd brake light back out and install some resistors in the wiring.

Whats happening is the LEDs in the 3rd brake light are making the truck think the brakes are on all the time...therefore not allowing the cruise control to stay on. A simple fix

Something similar to this:
http://www.google.com/products/catal...ed=0CFYQ8wIwAg

or this:
http://www.google.com/products/catal...ed=0CFgQ8wIwAw


Just be sure to research how many you will need and how to install them properly. Hope this helps

techrep

iTrader: (1)

Bucko speak's the truth !!

Mod (Ret.)

It has to do with load resistors. Most LED bulbs do not have them, and the cruise control measures resistancecurrent draw in the brake circuit to operate the cruise.

As stated, this is a common problem which has many posts about it. The search function will retrieve which LED light assemblies work, and which don't. There's also a post (or 20) on how to install load resistors (I'm not a fan of that though, as you'd have to remove them to go back to conventional bulbs).

Don't forget to replace the flasher too, otherwise your turn signals will flash rapid.

Ford123

I'm going to look into the resistors I have a new relay for the turn signals I know my third brake light stays on dim and so does my map lights so I should only need one resistor right?

Buck

No you'd need to install resistors for each set of lights. I didn't worry about my map lights staying on real dim. I'd just worry about doing the resistor for the 3rd brake light unless the map lights staying lit dim bothers you. The resistor in the 3rd brake light wiring will fix the cruise control problem.

04fxdwgi

Sounds like a load resisitor is the proper course of action. What happens in this case is that there are circuits connected to lighting circuits, that use the reletively low resistance of the bulb fillament to completed a path to ground. As these secondary circuits are usually extremely small current draw, such as in sensor circuit, the fillament in the bulbs have a low enough resistance to complete the circuit, but not light the bulb up. When LED's are used to replace std bulbls, the impedance (resistance) of the the LED is so high, it is like and open circuit and it won't allow these secondary circuits to complete the circuit and you have an inoperable sense circuit, hence no cruise.

Go to any LED site (or even any Harley site that sells the LED lights) and you will find the load resistors for short money. I have used 10 watt /100 ohm ceramic or down to a 1 watt / 660 ohm resistors to do the job and they work just fine, depending on what is connected that needs a current path. Just need a current path for it to work.

Ford123

Awesome thanks I'll definitely do that

Buck

I like my explanation better. Thanks for the technical answer.

scobar

iTrader: (4)

I have searched this topic, it seems it can be the year of the truck or the bulbs used where you have issues with the cruise. No real leads on brands either way...