2003 silverado

u dont really even need a bypass for that truck since it is passlock 2.  cut the yellow passlock wire in half, and measure the resistance between the module side of that wire and the org/blk wire with the vehicle in reverse and the ebrake on.  put the key in start and let off, you will get a resistance value.  wire one relay like this:

85-ignition 3 output (-)

86-12volt constant

30-module side of yellow passlock wire with resistor on this wire

87- tap into org/blk wire

i always use this method rather than buying a bypass, passlock 2 is way easier than passlock 1, its pretty much impossible to bypass pass1 without a module!!