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2026. 6. 30. 작업

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Does a constant blown fuse always indicate a short?

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If the fuse is blowing as soon as you perform an action it's a short to ground. Multimeter won't do much good in this situation. It'll come down to wiring diagrams and visual inspection of the harness and connectors on the circuit. Unless you have a fancy tool that will find the short for you. It looks like fuse 21 powers a bunch of stuff, but since the fuse only blows when you turn the a/c on that narrows it down quite a bit. If you look at an a/c wiring diagram you'll see fuse 21 only powers the blower motors, blend door motor, the constant control relay module and the a/c pressure switches. Try unplugging the low side a/c pressure switch as it's the easiest to access and see if the fuse still blows. You may want to use a circuit breaker while testing. This will tell you if the problem exists south of the switch as I assume the wiring harness will run along the subframe and up to the CCRM. If the fuse stops blowing then it's time to follow the harness to the high pressure switch and