Testing Brake Switch Wires with Circuit Tester to Install Brake Controller on 2002 Toyota Tacoma

Question:

I recently purchaed a Primus brake controller and 4 to 7 plug installation kit from you. I have 90 installed the kit, but I cannot determine which of the four wires coming out of the brake pedal is teh cold side. the light on the included quickee tester does not light up at all on any of the four wires two blue and two green with stripes of various colors. could my tester be faulty? how can I test the tester? do i actually need to stap through the casing to the copper, or will the alligator clip pick up the ppower to light the light? I clipped it to a 9v battery and it did not light either, nor directly on the battery of the truck. alternatively, do you know the color of the cold wire on a 2002 tacoma, 6cyl., automatice, extended cab, 4x4? thanks

asked by: Don

Helpful Expert Reply:

The alligator clip on a circuit tester is so you can ground it to complete the circuit to light the test light's bulb. You will need to pierce through the wire insulation to get down to the copper strands to be able to test for power on a wire with the pointed end of the tester.

On your 2002 Toyota Tacoma the brake switch wire you need is likely a green wire with a white stripe.

expert reply by: Michael H