Signal trouble

[sk-kw]

Hi, New to the forum. I having trouble with an 89 KW t600. When I step on the brake my left signal comes on. This unit does not pull a trailer, has a flat deck. I believe there is a burnt out diode someplace. Can anyone direct me to a electrical diagram manual for this unit or have a suggestion. I have other electrical issues with it also so that's why I would like a manual.

Thanks have a good 1

 

[diehard]

does your left signal stay on or does it flash? does your signal work normally when not using the brake? could be there is a bad ground on the signal.

 

[ironmanwife]

Wiring Diagram For 89 Kenworth Truck .pdf Download

 

[sk-kw]

does your left signal stay on or does it flash? does your signal work normally when not using the brake? could be there is a bad ground on the signal.

Hi diehard
thanks for the quick reply
The signal stays on constant as long as you depress the brake. The left signal works normally otherwise.

I willl check out the ground more

Have a good 1

 

[sk-kw]

Wiring Diagram For 89 Kenworth Truck .pdf Download

Hi ironmanwife

thanks for the link will let you guys know how I made out when I get another chance to look at it

have a good 1

 

[gearjammer]

sounds a lot more like a short instead of a ground problem

 

[sk-kw]

Wiring Diagram For 89 Kenworth Truck .pdf Download

Thanks for the link ironmanwife
let you know how I made out

sounds a lot more like a short instead of a ground problem

Yeah thats what I am thinking also. but I checked it out as much as possible so I am leaning to the burnt out diode letting the current back-feed. Thanks for the suggestion gearjammer and I will post as soon as I figure it out

 

[Racer X 69]

If a turn signal comes on when you are activating the brake lights then it would appear that the brake lights are trying to get a ground through the circuit that is illuminating, and it is likely that the ground for the brake light circuit is corroded so much it isn't available or there is an open in the brake light ground circuit.

 

[bigyellowpete]

If a turn signal comes on when you are activating the brake lights then it would appear that the brake lights are trying to get a ground through the circuit that is illuminating, and it is likely that the ground for the brake light circuit is corroded so much it isn't available or there is an open in the brake light ground circuit.

Could also be someone has connected the brake light lead in with the signal lead at the pigtail. I would start tracing the wires from the signal and brake light back and see what was what.

 

[sk-kw]

If a turn signal comes on when you are activating the brake lights then it would appear that the brake lights are trying to get a ground through the circuit that is illuminating, and it is likely that the ground for the brake light circuit is corroded so much it isn't available or there is an open in the brake light ground circuit.

Thanks Racer X 9
I will double check the grounds

 

[sk-kw]

sounds a lot more like a short instead of a ground problem

I will keep checking for shorts but it seems to me like it is backfeeding through a diode

thanks

 

[sk-kw]

Could also be someone has connected the brake light lead in with the signal lead at the pigtail. I would start tracing the wires from the signal and brake light back and see what was what.

I will check the connections tomorrow. Geez i hope it would be that, Feel kinda stupid if it is
thanks everyone for your help so far