Trailer wiring Installing a trailer brake controller for the 1st time on this vehicle,thats tow ready,i do not have power to the controller. i have installed the 40 amp maxi fuse underhood but when checking for voltage inside by brake pedal fuse box , no power there except for the brakelight switch wire. where do i check next?

Congrats, you have found Ford's super secret fuse that drove everyone mad for years!

Check the feed wire from the brake light switch to the controler. What type of vehicle do you have. Different vehicles have different switches/relays that assist in the trailer brake systems.

If your Prodigy P2 brake controller is flashing 00 and .c, it could indicate an error with the brake controller's connection to the trailer or the brake controller itself. Here are a few things to check:

1. Verify Connection: Check that the brake controller is properly connected to the trailer's electrical system. Make sure the trailer plug is firmly seated in the brake controller and the tow vehicle's connector. Ensure the pins and sockets are clean and free of corrosion.
2. Check Brake Controller Settings: Verify that the brake controller is properly set up for your specific trailer's weight and braking system. Refer to the brake controller manual for the recommended settings.
3. Check Trailer Brakes: Verify that the trailer's braking system is functioning properly. Check the brake drums and shoes for wear and damage, and make sure the brake adjustment is correct.
4. Check Wiring and Fuses: Check all wiring connections between the brake controller and the trailer, as well as the tow vehicle's wiring and fuses. Make sure all wiring connections are tight and secure, and that all fuses are intact.

If you have checked these items and are still experiencing issues, it may be necessary to take your vehicle and trailer to a certified mechanic or dealership for further diagnosis and repair. The hot brake smell from the car brakes could indicate that the trailer brakes are not functioning correctly and that the tow vehicle's brakes are doing most of the work, which can lead to overheating and brake fade.

Hello Carol, The 7 way is for use with a brake controller and/or a trailer that has electric brakes. The 4 way flat is a basic trailer plug connector.
Connect as follows:
Green wire- Connects to the vehicles right turn wire harness & provides brake light and right turn signal on trailer.

Yellow wire- Connects to vehicles left turn wire & powers brake light & Left turn signal on trailer

White wire- Ground

Brown Wire- Tail/ marker/ license plate lights

The Blue, Red & Purple wires on the 7 way will not be used on the adapter, those are for brakes.

I hope this information is helpful.

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Trailer Wiring Diagrams 4 Way Systems

4 way flat molded connectors allow basic hookup for three lighting functions; right turn signal / stop light (green), left turn signal / stop light (yellow), taillight / license / side marker (brown) and a ground (white).

4 way tow vehicle side.
4 way trailer side.
5 Way Systems

Same as 4 way system listed above but adds a extra blue wire for brake signal or auxiliary power. Used on pop up camper trailers or utility / boat trailers.
5 way tow vehicle side.
5 way trailer side.
6 Way System, Rectangle Plug 3/4 inch by 1 inch 6 way rectangle connectors right turn signal (green), left turn signal (yellow), taillight (brown), ground (white). The red and blue wire can be used for brake control or auxiliary. Use on a small motorcycle trailer, snowmobile trailer or utility trailer. Can also be used as custom wiring on trailers with 3 light/wire systems. See "Tow Vehicle Taillight Wiring" below.
6 way tow vehicle side.
6 way trailer side.
6 Way Systems, Round Plug

Round 1 1/4" diameter metal connector allows 1 or 2 additional wiring and lighting functions such as back up lights, auxiliary 12v power or electric brakes. Note: The black (sometimes red) 12v and blue electric brakes wire may need to be reversed to suit the trailer. Check with a test light or VOM. Uses: horse trailer, travel trailers, landscaping trailer, car trailer, etc.

6 way tow vehicle side.
6 way trailer side.
7 Way Systems

Round 2" diameter connector allows additional pin for auxiliary 12 volt power or backup lights. Uses: heavy duty landscaping trailer, car trailer, boat trailers, horse trailer, travel trailer, construction trailer, etc. Check with a test light or VOM.

7 way RV flat blade tow vehicle side.
7 way RV flat blade trailer side.

Most likely the brown wire from the trailer connector is connected to a constant battery voltage source, and it should be connected to the vehicle running light circuit, however someone might have wired the trailer connector up that way on purpose so that the trailer does not draw power from the vehicle running lights and possibly damage the vehicle running light circuit. (Dodge/Chrysler vehicles do have delicate lighting systems) Here are some images to help assist you, and the 4 way connector is the same as the 5 way connector just without the blue wire for the trailer brakes.

You have got 7 pin trailer connector that was included in the optional trailer tow package. This trailer tow package also includes an electric trailer brake wiring provision that terminates at a connector located on top of the large body harness connection under the instrument panel to the left of the break pedal, as well as an electric trailer brake pigtail harness and an instruction card that are stored in the glove box when the vehicle is shipped from the factory. You will need to add an electric brake controller of your choice that will plug-in to the harness and that will also give you power on your auxiliary circuit.

Did you check bulb in trailer.. Some have multiple elements for brakes and signals.. One can work while the other dosent.. .

if your vehicle lights are working all the fuses will be good. follow the cable from the towing socket on your vehicle , it will most likely go behind one of the rear lights to connect into your cars system,
check your tester where the cables join and you should find the problem. hope this helps.

what type controller did you install? Is this a camper or trailer? Is the controller hydraulic plumbed into master cylyder? Important to know how to adjust rheostat for sensitivity. If set at minimum the system is basically on the edge of not sending any signal to towed unit. The intructions should explain how to make this adjustment. If set too sensitive trailer brakes will lock up before the tow vehcle starts to brake. Controller should be set so trailer starts braking just befor the tow vehcle. If not the trailer will tax the tow vehicle brakes by pushing. Its set right when you feel the combination stretching out. trailer first then tow vehcle. Good luck and remember, if truck brakes first and too hard you risk a jacknife. All light voltages should be system voltage. Brake voltage is variable depending on setting on controller. Understand your breakaway brakes and how they work. breakaway breaks require an auxillary battery. Again, good luck and you know where to find me if I can be of anymore help.