A fuse blows when there is too much current drawn thru it. Let's say it is for the radio. If the radio is turned off and the fuse blows immediately then the power wire to the radio has a bare spot somewhere and is touching the metal of the car or the power wire is touching the negative wire. If it blows when you turn it on then the radio has a short inside or a malfunction causing it to draw too much current.
Let's say it is for the dome light. If you put the fuse in with the door closed and the dome light is set for DOOR and blows right away then the short is in the wire leading to the door switch or the switch is shorting out, letting + touch the - metal body of the car. The entire body is negative. That is why there is usually only one big thick black wire on the battery for negative. If the fuse blows when the door is opened, then the switch is probably shorting out, or the wires going to the dome light.
Generally when the fuse blows when you turn something on, then whatever you are turning on is probably junk, unless it is a stereo that draws too much power for the thickness of the wire, or the stereo is junk.
305 views
Usually answered in minutes!
×