Car Alarms: under steering column wires, digital multimeter, starter wire

Question
can you tell me what gauge the starter wire should be... I don't have the multimeter.  Or do you know where I can get a wiring diagram for my grand cherokee?
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-----Question-----
I spliced a wire into a Pink and Black wire that is supposed to be the Accessory wire. (my guide says that the accessory wire should be red and black). I am going to splice another wire into the starter wire... I cannot find the same gauge wire that is yellow.(according to the guide, the starter wire is yellow)
-----Answer-----
You should ALWAYS use a digital multimeter to verify the function of a wire PRIOR to splicing into it.  Just because the wire is the same color that is listed in a wiring chart does not mean it is the right wire.  Your starter wire will only have +12V when the key is in the 'start' position, your accessory wires will only have +12V in the on and run position but not start, your ignition wires will have +12V in all positions but off, and your constant +12V wires will have +12V no matter what the position of the switch.  Newer vehicles have control modules that are delicate and can not handle receiving voltage on the incorrect wires, possibly damaging expensive components.

Answer
The starter wire may be a smaller gauge than the other wires in the harness because it does not need to be as heavy since it is only supplying a solenoid.

I would really prefer you pick up a digital multimeter, or at least a test light that uses L.E.D.s instead of a regular bulb to reduce the risk of hurting components.

If you do not have a way of testing the wires you run a severe risk of permanently damaging your vehicle.  I really recommend not continuing until you have the proper tools to complete the job.

If you still want to continue without the proper tools, head over to http://www.the12volt.com/installbay/vehicles.asp and you can find another wiring chart to compare with the one you already have.

Keep in mind that if you splice into an airbag wire and apply +12V to it you will cause the airbag to go off, if you provide +12V to a BCM wire you could fry the computer that controls the vehicle.  Please consider borrowing/getting a multi meter before you continue.