Tekonsha Primus IQ Trailer Brake Controller # TK90160 Blowing Fuse on 2015 BMW X5

Question:

im installing a trailer braking module on a 2015 bmw x5. Ive ran a 20 amp fused power wire, brake light signal, good ground. The unit turns on but as soon as I press in the manual brake slider the fuse blows. I connected another unit the tekonsha prodigy and it doesnt blow the fuse. Ive also tried another primus iq 90160 and it still blows. All my wires are good no shorts to ground.

asked by: Andrew

Expert Reply:

I spoke with my contact at Tekonsha and in order to correct the issue of the circuit being overloaded when installing the Primus IQ Trailer Brake Controller, # TK90160, on your 2015 BMW X5, you will need to install a Pulse Preventer, # 5501. The pulse preventer will need to be wired backwards which will allow power to come from the vehicle but will block power from coming out of the controller and back to the vehicle.

Once you have installed the pulse preventer, I recommend taking your vehicle and trailer on a short test drive to make sure that the Primus is now functioning properly.

The reason that you did not experience the same issue with the original style Prodigy is the fact that when using the manual override on that unit the brake lights are not activated therefore no back-feed and blown fuse.

expert reply by: Leah S