Truck Brakes Don't Activate Trailer Brakes With Primus IQ
Question:
The Primus works but when pressing on my truck brakes they don’t activate the trailer brakes.
asked by: Dave H
Expert Reply:
If the trailer brakes are not activating with your Tekonsha Primus IQ Trailer Brake Controller # TK90160 when you hit your truck brakes, you will need to troubleshoot the issue and I'll go over how to do this. You will need to find out if the issue is on the brake controller, truck, or trailer. To test the brake controller, sever the blue wire a couple inches from the back of your controller. Then use circuit tester # PTW2979 to test the end of the blue wire coming out of the controller. It should only have power when you apply the manual override; if it shows power at idle then there is an issue with the controller and it will need to be replaced.
If the controller tests fine, reconnect the blue wire and move on to the truck side trailer connector. Often, corrosion or dirt may be the cause of a short in a trailer connector. Check the plug to see if there is any type of corrosion built up that may be hampering its functionality.
You will also want to test the brake output pin on the 7-way socket; it should only show power with the manual override. If it shows power any other time then there is a short somewhere between the connector and the brake controller you will need to find.
If the truck side checks out then it could be the wiring to the brake magnets or possibly the magnets themselves. Inspect the power wires to the magnets and look for wires that may be pinched or otherwise damaged and fix as necessary. You'll also need to make sure the ground wires are attached to bare metal surfaces and free of any paint, dirt or corrosion.
Products Referenced in This Question
Product Page this Question was Asked From
Tekonsha Primus IQ Trailer Brake Controller - 1 to 3 Axles - Proportional
- Trailer Brake Controller
- Proportional Controller
- Electric
- Automatic Leveling
- Under-Dash Box
- Dash Mount
- Up to 3 Axles
- LED Display
- Up to 90 Degrees
- Tekonsha
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