LBZ: cruise won't stay on when my lights come on.

[MOJO]

Guys I have a question for you, my cruise won't stay on when my lights come on (Auto Lights) I have my cruise set at 65mph driving home yesterday with a load of lumber and it was getting dark as soon as the lights came on the cruise went off? Lights all work just fine so I am at a loss.



Truck runs fine no problems that I can see, I did have a trailer taillight out but I can't see this being the problem. Wires look fine could this be a Fuse problem? Like a low current draw? Thanks For the help upfront Jim

 

[chevyburnout1]

Did you verify that the cruised worked again after you turned the lights back off? Then it disabled it again when you turned the lights back on?

 

[MOJO]

It was strange as soon as the lights came on the cruse went off. I thought what happen so I hit the cruse button NOGO! So I turn off the lights guess what it works The only thing I could come p with was a blowen trailer tail-light bulb. I will know this weekend when I hook up again.

 

[Chevy1925]

It was strange as soon as the lights came on the cruse went off. I thought what happen so I hit the cruse button NOGO! So I turn off the lights guess what it works The only thing I could come p with was a blowen trailer tail-light bulb. I will know this weekend when I hook up again.

disconnect the trailer and try it again. you would be surprised what kind of havoc trailer wiring can do to a truck.

 

[Amys2k11LML]

This is very interesting, would love to know the out come, please be sure to post the final findings! Good Luck!!!!

 

[02greysixer]

disconnect the trailer and try it again. you would be surprised what kind of havoc trailer wiring can do to a truck.

X2 I have one trailer that when I turn on the left blinker all my dash lights flash with the turn signals :rofl: They do some strange things for sure.


Sint frum tha orijinul smert fone

 

[Kartmnn]

My 2000 1500 4.8 5 speed totally lost the odometer and flasher because of trailer lights. As soon as it was unpluged the truck went back to normal. :thumb:

 

[Sledheadxp800r]

My cruise will shut off every couple miles when I tow my friends trailer. Any other trailer I tow the cruise never shuts off.

 

[DAVe3283]

A faulty trailer WILL shut off the cruise control and do all sorts of random things. Why?

The trucks don't use any sort of diode protection on the trailer plug. So if the trailer has a short (or partial short) from the running lights to the brake light circuit (can be caused by a bad ground on any one of the trailer lights), the truck sees some voltage on the brake circuit, and shuts off the cruise control just like you tapped the brakes. It is a safety thing.

If the trailer has other shorts, it can make brakes turn on turn signals, vice versa, and all sorts of random things. I once had a trailer cause my left turn signal to activate the four-way flashers on the truck, but not on the trailer...

This could be solved with some diode protection on the trailer plug, but that is (sort of) expensive and complicated. Actually, I don't know of any manufacturer that does it.