What are some reasons that a fuse would blow?

[Shel_B]

The Camry had a blown fuse for the power port for a while - since I bought the car, I suppose - but I didn't know about it until I tried to use the power port to charge my phone many months after purchasing the car. Well, I chased down the problem and replaced the fuse, and all seems to be working just fine now.

However, I'm curious as to why that fuse, or any fuse, might blow. It would be great if there's something I can check to be sure there's no underlying problem and that the issue doesn't come up again. Thanks!

 

[ripcord]

The main reason is a dead short somewhere. Other reasons are continuous high draws that overheat the fuse without blowing it all at once.

You might have a bare wire somewhere or someone could have plugged in a device that had an internal short, or perhaps was using a 12v inverter to power a high wattage device.

 

[nomas]

The only thing that will blow or melt a fuse is excessive current . However it may happen , it's still all about the current . Find the source of the current .

 

[atikovi]

Usually the fuse blows when the power conductor touches a ground, be that from a frayed wire in the circuit or something internal to the device being plugged in.

 

[Shel_B]

There are two power ports in the car, and one is in a space in the center console. I found some miscellaneous metal pieces in the power port ... a coin, a small screw, a paper clip. Of course, that got cleaned out, but I'm wondering if that could have caused the fuse to blow.

 

[PontiacHO]

Loose connections can cause blown fuses when the power is “making and breaking” connection.

 

[ripcord]

There are two power ports in the car, and one is in a space in the center console. I found some miscellaneous metal pieces in the power port ... a coin, a small screw, a paper clip. Of course, that got cleaned out, but I'm wondering if that could have caused the fuse to blow.

Absolutely!

 

[nomas]

Look at the fuse element if it is visible . Did it just burn open , or did it " blow " and leave nothing but silver splatter ? Sometimes that can be a clue to help you troubleshoot .

 

[Shel_B]

Absolutely!

I was hoping that could be the cause. I suppose time will tell ... thanks for the quick response.

 

[Shel_B]

Look at the fuse element if it is visible . Did it just burn open , or did it " blow " and leave nothing but silver splatter ? Sometimes that can be a clue to help you troubleshoot .

The fuse is long gone, can't check it.

 

[Luftmasse]

2 main reason why a fuse would blow:

1) Short to ground.
2) Amperage of the circuit went over its capacity.

 

[supton]

Want to say, bad connection to the fuse can do it too--the bad contact makes heat, which can make the fuse melt. Had an Isuzu years ago with fuse box under the hood, and it lose a fuse that way, contacts were nearly corroded away.

Probably not the issue here though.

 

[eljefino]

It was a coin or similar thing in the hole.

 

[Soft Cars]

More current flowing in the circuit than it's supposed to have.

The current flows through the fuse and reaches ground before it passes through a resistor.

Current takes a short cut through the gas station on the corner instead of waiting for the light to turn green for traffic to clear.

 

[mrbreezeet1]

Sometimes a penny or another foreign metal object falls down into the charging port too!

 

[Trav]

There are two power ports in the car, and one is in a space in the center console. I found some miscellaneous metal pieces in the power port ... a coin, a small screw, a paper clip. Of course, that got cleaned out, but I'm wondering if that could have caused the fuse to blow.

This is very common since people toss coins and all sorts of stuff in places where these ports are. Most of the time they don't even know it until the OBD 2 port is non functional, some take power from it. Otherwise excessive current draw from things like tire inflators or a dead short are the other reasons.

 

[mrbreezeet1]

There are two power ports in the car, and one is in a space in the center console. I found some miscellaneous metal pieces in the power port ... a coin, a small screw, a paper clip. Of course, that got cleaned out, but I'm wondering if that could have caused the fuse to blow.

Absolutely it could cause it!

 

[D60]

It was a coin or similar thing in the hole.

Was gonna say a kid stuck something metal in there. The power ports are like a game of Operation - easy to short