willald wrote: ...Based on some recent discussion via PMs, I was just wondering, thought I'd throw this out for ideas:
How would one wire the LED indicator on the MH dash to work off of the towed vehicle's brake pedal being engaged, if its a case where the toad battery has to be disconnected when towing?
If battery is disconnected, most approaches I've seen to this would not work. Tapping into trailer wiring, tail light, or brake switch won't work, as there's not going to be 12Volts on any of them, even when brake pedal is pushed.
I wonder if this is why ReadyBrake went away from wiring their LED indicator to work off of the toad's brake switch?
Will
Just got off the phone with RB's owner (Tod) and he says they changed the indicator setup because so many were pulling fuses on their toad.
As for the two wires coming back from the coach dash indicator light, it's nothing more than a ground return, so any way that you can close that circuit to ground from the toad's brake pedal will work. If one was to use the third brake light, then a relay would work by then using the N.O. contacts to close the ground return. The brake pedal may very well have a ground return within itself or maybe use another switch, mech. or pressure with a set of contacts to close this ground return.
"We are often so caught up in our destination that we forget to appreciate the journey."
1998 36ft. National Tropi-Cal Model 6350 on a 1997 Chevy P32
Chassis_7.4 Vortec Engine_4L80E Tranny_slide_tag axle.
willald wrote: ...Based on some recent discussion via PMs, I was just wondering, thought I'd throw this out for ideas:
How would one wire the LED indicator on the MH dash to work off of the towed vehicle's brake pedal being engaged, if its a case where the toad battery has to be disconnected when towing?
If battery is disconnected, most approaches I've seen to this would not work. Tapping into trailer wiring, tail light, or brake switch won't work, as there's not going to be 12Volts on any of them, even when brake pedal is pushed.
I wonder if this is why ReadyBrake went away from wiring their LED indicator to work off of the toad's brake switch?
Will
Since the RB light wires directly to the MH's hot wire, and the ground wire is what is switched, you must find a way, or add a switch to the towed's brake pedal, that will connect to ground when the brake pedal is pressed. The light is dependent on a ground being completed, and the only moving part available to complete the ground is the towed's brake pedal.
I used a 12v relay between the towed's trailer wiring and ground to activate the N.O. (Normally Open) circuit, however, that requires the towed's battery to be connected.
Bobbo, Linda and the furry kids (1&1/2 German Shepherds)
2007 Winnebago Outlook WF331C on a Ford E450 Super Duty Chassis
2010 Subaru Forester w/BlueOx baseplate & Ready Brute Elite towbar
Bobbo wrote: Since the RB light wires directly to the MH's hot wire, and the ground wire is what is switched, you must find a way, or add a switch to the towed's brake pedal, that will connect to ground when the brake pedal is pressed. The light is dependent on a ground being completed, and the only moving part available to complete the ground is the towed's brake pedal.
Right. Challenge is, doing that and making it work when battery is disconnected, yet without causing a short or other problem when the brakes are depressed when toad battery IS connected.
Isn't the brake switch going to be connected to + side of battery on one side (the 'hot' side), and have 12V going through it when battery is connected and brake is pressed? That being the case, if you connect to that switch and use it to close a connection to ground for the LED indicator, you're going to cause a short that will blow a fuse when the battery is connected and brake pedal is pressed (right?)
That seems to rule out using the existing brake switch, doesn't it?
If toad battery has to be disconnected, seems like only way to make this work would be to install a second switch of some kind on the brake pedal. Or, what am I missing here?
In my '07 Saturn Vue, when you pull the fuse for the ignition (in my case,toggle the switch I installed), there is still 12v to the brake lights and switch. I cut the two wires (positive and ground) from the RB actuator and ran the positive back to the positive on the toad brake light switch. I connected this to the power feed for the LED on the motorhome dash (which had been connected to the coach 12v) and grounded the other LED wire under the dash. Now, when the toad brakes are actuated by the RB, 12v is sent to the brake lights and the LED.
So what if you essentially reverse the way the light is wired? Instead of switching the ground side, you are switching the hot side.
Power the brake light switch from the motorhome through a separate wire that is disconnected when not towing,pick up the "switched" power from below or after the BL switch contacts.
I cannot see any conflict with the Cool Tech harness since nothing is running through it or the brake pedal switch currently.
Bobbo wrote: Since the RB light wires directly to the MH's hot wire, and the ground wire is what is switched, you must find a way, or add a switch to the towed's brake pedal, that will connect to ground when the brake pedal is pressed. The light is dependent on a ground being completed, and the only moving part available to complete the ground is the towed's brake pedal.
Right. Challenge is, doing that and making it work when battery is disconnected, yet without causing a short or other problem when the brakes are depressed when toad battery IS connected.
Isn't the brake switch going to be connected to + side of battery on one side (the 'hot' side), and have 12V going through it when battery is connected and brake is pressed? That being the case, if you connect to that switch and use it to close a connection to ground for the LED indicator, you're going to cause a short that will blow a fuse when the battery is connected and brake pedal is pressed (right?)
That seems to rule out using the existing brake switch, doesn't it?
If toad battery has to be disconnected, seems like only way to make this work would be to install a second switch of some kind on the brake pedal. Or, what am I missing here?
Will
That is the reason that my earlier post included the phrase "or add a switch to the towed's brake pedal".
UPDATE: Decided that I wanted to retain READYBRAKE's system as well as some extra wiring for the toad's brakes. I put a small 12v relay on the third brake light and used it's dry contacts to complete the ground circuit which in turn activates the RV dash light and only when the brake pedal is actually depressed on the toad. This way, there's no conflict with hot or ground mistakes and no changes to the original system wiring. Only needed to run a two conductor cord through the driver's side frame as I did with the COOLTECH harness and the easiest way if you have a fish tape handy. Attached a connector at the front which is hidden when not in use behind the DEMCO dress caps on the base plates. Then ran a section of this cord alongside the the COOLTECH umbilical cord with connectors on both ends of that. Now I can plug in to the toad or to the surge actuator at my discretion and after a long trial run, it appears that default will be the toad, rather than the READYBRAKE actuator. Even carry a spare relay that can easily be changed out if need be on the road, but still like the option of switching over in an instant in case of any problems. The whole install was pretty easy and with no real mods to any of the toad's wiring. Even with the relay, I sort of used a plug and play connection, so there is no cutting or splicing of any kind.
Still don't know how to attach pictures here, so any help with that would be appreciated.
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