How Much Power Does the Tekonsha Primus IQ Pull from the Brake Light Switch

Question:

I got my Primus IQ ready to install in my 2015 Highlander, but a tech at the RV service said that with some new pushbutton start vehicles the hot line to the brake pedal might be only 5 volts not 12. If that is the case he said the brake controller would try to take 12v from the 5v feed and could cook the electronic board on the car. Is this true? Thanx.

asked by: Dale F

Expert Reply:

The Tekonsha Primus IQ # TK90160 will actually connect to the battery on your 2015 Toyota Highlander for the 12V Power using the Black Wire and a 20 Amp Circuit Breaker # PK54520. The Red wire will be run to the COLD side of the stop light switch. This is the wire that only gets a signal when the brake pedal is pressed. You can use a Circuit Tester # PTW2992 to find this wire if you do not already know which one it is.

The Blue wire on from the Primus IQ will be run to the connector at the rear of your Highlander to connect to your trailer, and the White wire will be run to the negative terminal on your battery.

The Primus IQ only connects to the COLD side of the stop light switch which acts like a trigger. It doesn't pull voltage from this; it pulls the voltage directly from the battery. Even if the stop light switch on your Highlander only receives 5V of power it will not do any damage.

I have attached a photo of how the Primus IQ will need to be wired for you to follow as well as an installation video of it being installed on a 2013 Highlander.

expert reply by: Jon G