Amp gauge problem

Well think of it as a ballast resistor in some aspects. You pass all of the current in the car through them. They will get warm. Also they can be shorted out when removing the dash if you do not disconnect the battery first. I know I shouldn't have to say that but you won't believe how many people do it. The worst part of them is that if it goes out on you in the middle of the night you can't fix it. If you have the tools you can disconnect the two wires and hook them straight together. But how many of us have the tools in our cars to take the insturment cluster out in the middle of the night. The wiring industry frowns on the use of them for many reasons, mostly the ones listed above. Also if you use anything rated higher than the stock alternator you will cook the ammeter like rickity tick!