Basic wiring toad lights - Left, right, and tail lights.
On two of my Toads, I tapped into the toads left, right, and running lights up front, and installed a flat 4 female connector that is under the hood of the toad. I did not use diodes to isolate the MH from the Toad. The only ramifications of this, if I turn on the Toad lights, they will also power the MH lights. The flat four connector is exactly the same that you would find on the back of the car, and plug your trailer into. The 5 ft long cord that connects the MH to the Toad has a flat four Male connector on both ends. I plug it into the MH, then plug the other end into the Toad connector.
One of the positives, I can see the toad lights work in my rear view camera.
On my Saturn Vue - I also tapped into the toads lights up front, but installed a 7 pin connector instead of a flat four.
Special wiring for BRAKE SYSTEM -
On my Add-A-Brake (toad brake system) - It detects when the MH brakes are being applied by looking at the left, right, or brake light signal coming from the MH (depending how the MH is wired to the toad)
On my Vue, I don't have a "brake" light electrical wire coming from the MH, so its wired to monitor the Left and Right turn signal lights, that also serve as the brake lights. The brake system is smart enough to know to ignore the turn signals. If it sees the light turning on and off, It knows this is a "turn signal". But if it sees the light stay on for more than a couple seconds, it interprets this as being a "brake Light" and applies the toad brakes.
The brake system releases the toad brakes when the brake light signal goes away.
One of the problems with detecting MH brakes by looking at the brake lights, if the toad brake lights are wired to the MH brake lights. When the brake system presses the brake pedal and the toads brak lights come on, the brake system could get confused and think the MH brakes are still applied, because the brake system see's the brake lights are turned on.
The brake system has some special wiring that may need to be implemented to prevent this from happening. (add a switch or relay to isolate the toad brake lights)
On my Vue, the brake lights are separate from the turn signal lights, so this isn't a problem. and I didn't need to do any special additional wiring.
2001 Coachmen Mirada (Ford F53 6.8L V10) - Toad 2003 Saturn Vue
It won't do MACH 2, but I can get a sandwich and take a pee.