BigBrother-84 Posted May 28, 2023 Share Posted May 28, 2023 Hi Gentlemen, Just for fun, am I the only one who have the Hazards sending an intermittent "brake pulse" to the trailer brake controller? I realized that couple of years ago, coming back home, truck loaded, pulling a heavy horse trailer and climbing a steep hill on a highway. Losing speed, I turned on the Hazards. The trailer brakes were applied with each Hazard's pulsation. A mechanic told me it's normal for these Ol'Trucks, but I am wondering if he was correct. Link to comment Share on other sites More sharing options...
Gary Lewis Posted May 28, 2023 Share Posted May 28, 2023 Interesting! Yes, if your trailer brake controller is triggered from the brake lights then the hazards would trigger it as well. Hadn't thought of that. You could fix that with a diode in the brake wiring just downstream from the brake switch, and then tie the brake controller in between the switch and the diode. But your lights would be slightly dimmer due to the .7V drop across the diode. Link to comment Share on other sites More sharing options...
85lebaront2 Posted May 28, 2023 Share Posted May 28, 2023 This is exactly why I kept this controller for Darth: It is a Kelsey-Hayes hydraulic actuated controller, unfortunately, no longer available. Here is where it connects to my late master cylinder: Link to comment Share on other sites More sharing options...
BigBrother-84 Posted May 29, 2023 Author Share Posted May 29, 2023 Interesting! Yes, if your trailer brake controller is triggered from the brake lights then the hazards would trigger it as well. Hadn't thought of that. You could fix that with a diode in the brake wiring just downstream from the brake switch, and then tie the brake controller in between the switch and the diode. But your lights would be slightly dimmer due to the .7V drop across the diode. Happy to see that it's not a Big Brother's only problem. You could fix that with a diode in the brake wiring just downstream from the brake switch, and then tie the brake controller in between the switch and the diode Smart idea, as usual Gary! This is exactly why I kept this controller for Darth Bill, these controllers had hydraulic only for activation (the rest being electrical to the trailer), or was there a complete hydraulic system going to the trailer's brakes? Link to comment Share on other sites More sharing options...
FuzzFace2 Posted May 30, 2023 Share Posted May 30, 2023 Bill, these controllers had hydraulic only for activation (the rest being electrical to the trailer), or was there a complete hydraulic system going to the trailer's brakes? Only for activation. There was a slave cly type thing inside that moved the knob that moved across a resister that then sent power to the trailer brakes. I am sure that type controller went away when ABS brakes came out on cars & trucks. Dave ---- Link to comment Share on other sites More sharing options...
85lebaront2 Posted May 30, 2023 Share Posted May 30, 2023 Bill, these controllers had hydraulic only for activation (the rest being electrical to the trailer), or was there a complete hydraulic system going to the trailer's brakes? Only for activation. There was a slave cly type thing inside that moved the knob that moved across a resister that then sent power to the trailer brakes. I am sure that type controller went away when ABS brakes came out on cars & trucks. Dave ---- Dave, you are correct on both counts. I have had that one since I had my 1977 F150 and needed to use a friend's car trailer. The electronic ones were just becoming more common then. When I bought Darth, he had an electronic one with a pendulum in it to determine how much power was needed for the brakes. I was taking our 30 ft. 5th wheel back to the dealer for some warranty work not long after buying Darth, I was on US 17 in York County VA, at an area where the pavement is a little rough and had to stop for a light. Until that point the system worked pretty well, rough pavement + brakes + pendulum rheostat = pulsing trailer brakes to the point I was worried about damaging the brakes. I went back to my trailer specialist in Hampton VA and asked about a different controller. At that time (1994) the all electronic ones that were close to what a $60 hydraulic one in performance, were well over $300, they're less expensive now, but as long as this one (a) doesn't leak and (b) still works, I do not plan on replacing it. Link to comment Share on other sites More sharing options...
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