Installing a Brake Controller From Scratch on a 1989 GMC 1/2 Ton Pickup
Question:
Looking for info on how to install an electric brake controller on a 1989 GMC Wrangler 1/2 ton truck.
asked by: Bruce
Expert Reply:
To install an electric brake controller on your vehicle, you will need three items to complete installation. First, a brake controller. We have numerous brake controllers to choose from but I recommend our most popular model, the Tekonsha Prodigy, # 90885. You will also need the 7 and 4 Way Installation Kit, # ETBC7. Finally, you will need 4-Pole Hardwire Kit Including Circuit Tester, # 18252.
You will need to first install the 18252 wiring harness. Installation is fairly simple. Using the included circuit tester, you will need to hardwire the 4 pole by function. Turn on the left blinker. In the taillight assembly, find the wire with the tester that blinks with the signal. Connect this wire to the yellow wire on the harness. Next, do the same with the right signal. Connect this wire to the green wire on the harness. Next, turn on the lights. Find the wire that carries this signal and attach it to the brown wire on the harness. The white wire is ground. Connect it to the vehicle frame or another available grounding point. After that harness is installed, we can begin the ETBC7 and brake controller installation.
You will start by wiring the 7-Way trailer connector. Plug the 4-pole adapter coming out of the 7-way connector into the vehicles 4-pole trailer connector (from the 18252 you just installed). Ground the 7-Way white wire onto the vehicle frame. Connect the black wire in the grey duplex cable to the black wire on the 7-Way. Then, connect the white wire from the duplex to the blue wire on the 7-Way. Next, you will route the duplex cable under the vehicle to the engine compartment.
Next, mount the brake controller where you will have easy access to it using the bracket and screws provided. I have included a link to the instructions below.
Last, make the connections from the brake controller to the vehicle. On the duplex cable, separate the white brake wire from the 12-volt black wire. The white wire gets routed through the firewall, under the dash, into the vehicle. This wire connects to the blue wire from the brake controller. The black wire gets connected to the positive battery terminal via a 40 amp circuit breaker. Mount the circuit breakers under the hood or dash then route the black hot lead to the 40 amp breaker via ring terminals and then to the positive battery terminal.
The black wire on the brake controller connects to a 20 or 30 amp circuit breaker (see the brake controller instructions for which circuit breaker to use) and then to the positive battery terminal. Route the brake controller white wire to the negative battery terminal. From the wires connected to the brake switch at the top of the brake pedal, find the wire carrying a signal only when the brake pedal is engaged. You will need a circuit tester like # PTW2992, or the one that came with the 18252 kit. Connect that wire to the brake controller red wire.
I have also included an FAQ on Wiring A Brake Controller from scratch that will guide you through the process.
Products Referenced in This Question
4-Way Flat Trailer Connector w/ 72" Harness, Circuit Tester and Wire Taps
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- No Converter
- 6 Feet Long
- Universal Fit
- 4 Flat
- Tekonsha
more information >
Tekonsha Prodigy P2 Trailer Brake Controller - 1 to 4 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Electric over Hydraulic
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 4 Axles
- LED Display
- Up to 360 Degrees
- Tekonsha
more information >
Product Page this Question was Asked From
Universal Installation Kit for Trailer Brake Controller - 7-Way RV and 4-Way Flat - 10 Gauge Wires
- Accessories and Parts
- Trailer Brake Controller
- Installation Kits
- etrailer
more information >
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