How to Wire a 1990 Ford F-150 for a Brake Controller


i have a 1990 ford f150 w/o tow package installed a hitch, have wiring harness for a 2004 ford f150 is there a plug on my 90 so i can just plug brake controller in

Expert Reply:

Since your vehicle does not have a towing package you will need to install a T-One Vehicle Wiring Harness with 4 Pole Trailer Connector part # 118316. First, locate the vehicle taillight wiring harness along the inside of the left rear frame rail. This harness will have a connection point with connectors matching the ends of the T-connector adapter. Separate the harness connectors, being careful not to break the locking tabs. Insert the T-connector adapter between the harness connectors and lock into place. Be sure that connectors are fully inserted with locking tabs in place. I have attached detailed instructions below for installing this part also.

You will also need to purchase an Brake Controller 7 & 4 Way Installation Kit - 10 Gauge part # ETBC7.

Now, you will want to install the connector that came with your ETBC7 kit near the rear of your truck in a location that will be convenient for your trailer wire to connect to.

Plug the 4-way on the back of the 7-way connector into the 4-way that was just installed on the vehicle. Next, you will ground the white wire with the ring connector to the chassis. Then, using the double bonded 10 gauge wire connect the black wire to the black wire on the 7-way connector and connect the white wire to the blue wire on the 7-way connector. Run the double bonded wire forward into the engine compartment avoiding areas that could melt, cut or pinch the wires. Then, connect the black wire through the included 40 amp circuit breaker to the positive battery post, and run the white wire through the firewall to the blue wire on the back of the brake controller. The final wire on the trailer connector will be purple or yellow and can be used for surge coupler lockout and/or a reverse light circuit if needed. If not needed it can be tied up out of the way.

I have attached directions for the ETBC7 kit also.

You will not be able to use a harness from a 2004 Ford F150 in your 1990 Ford F-150

Now, inside your F150 you need to wire the brake controller. First, you will need to use a length of the double bonded 10 gauge wire that is left over from the wire ran previously and connect the white ground and black power wire from the controller to the white and black wires in the double bonded wire. Then, run these wires through the firewall to the battery. Connect the white wire to the negative battery post, and connect the black wire to the positive battery post using a 20 or 30-amp circuit breaker. See brake controller instructions for correct size circuit breaker. Then, you will need to find the stoplight circuit behind the brake pedal under the dash, this wire will have power only when the brake pedal is pressed. Connect the red wire from the brake control to the stoplight switch circuit that you discovered previously by using a circuit tester, part # 3808, and applying the brake to discover the needed wire.

Important note: If your truck is equipped with an anti-lock brake system you should NOT connect to the stoplight switch. The wire you need to connect to is a light green wire in the turn signal harness connector under the dash near the steering column. It will be the second wire from the left on the top column of the crescent shaped connector. I have included a set of directions for installing a Draw Tite 2 brake controller that show what the connector looks like, it will be on the second page of the directions.

I have also included a video that shows how to complete wiring on a 1990 Ford F-150 with anti-lock brakes for a trailer.

expert reply by:
Jameson C

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