just wanted to know how bad is it to put a 30 watt fuse into a 15 watt slot?

my dome light fuse blew again and the only spare i have is a 30. i havent put it in yet, but will that damage it?

 

If you know *why* the fuse blew (i.e. cause you shorted something accidentally) then putting a larger fuse in there temporarily isn't going to hurt anything. It would just take more amps to blow that fuse. Just be careful not to do what you did the first time to blow the fuse.

However, if you did nothing to blow the fuse, or you don't know why it blew in the first place, then by all means do *NOT* put a larger amp fuse in there.

Fuses blow for a reason. If you don't know the reason, and put a larger fuse in there, what will happen is instead of the fuse blowing when it is supposed to, the circuit will draw more power, and wreck something else. It is far easier to replace a 5 cent fuse, then to replace wiring, housing, etc etc.

 

the only reason i can think of is that i connected courtesy lights in my side mirror to come on when a door opens or when i unlock the door. i used side markers with a 194 bulb. do you think putting on a 30 fuse would be better?

the weird thing is, i put the side marker on like 2 or 3 months ago without a problem, and only recently have 2 blown in 2 weeks.

 

I'd ask engifineer.....he;s liklely to be your best bet on this subject. Tell him I sent you

 

If you blew a 15 amp fuse, you have something SERIOUS wrong. Placing a 30 amp in there could set your car on fire. Find out where the short is...you have a short somewhere on that circuit

 

Definitely double check all your wiring for shorts to ground, shorts to power, shorts to other wires before putting a new fuse in! Make sure you can duplicate the exact conditions of when the fuse blows while checking for shorts.

 

If that's all you added, the fuse isn't blowing because it's overloaded. You have a short or something. You need to find the reason.

 

Hells yeah it's bad!!

Find the fault! Don't just throw a replacement in there!
Not even a 15amp!!

 

So I'm thinking about this...it's worrying me because I can
imagine your box burning up...

Tell me how exactly you ran those wires for the lights?

In grommets?

Around Grommets?

No Grommets?

What's a Grommet?

 

Amen to that

 

its going around the grommet.

 

hmmm... after i got my new headunit installed, it wouldn't turn on and it kept blowing the 7.5amp fuse. i put a 10amp fuse in there and its been working fine. my guess is that the new headunit needed more power.?

 

OEM fuses are sized to protect the wiring not to protect whatever load is connected.

Normal wiring is sized to handle the expected load, plus just a bit more - this is it's built-in safety factor.

Wires, especially those in bundles with other wires where they ALL heat up just a bit under load, and the heat can't escape easily, can very easily have their insulation melt, or even catch fire. Even just putting wires into a bundle, or covering them with anything that might hold in heat, reduces the amount of current they can safely carry.

(As an example, the NFPA National Electrical Code shows how much one has to derate power wiring if it is put into a conduit rather than open-air run. It is derated even more if additional wires are in the same conduit. BTW, "NFPA" is National Fire Protective Association.)

If your fuses worked fine for months after adding load to the circuit THEN started blowing, it is NOT the load, it is a problem.

DO NOT put a larger fuse in a circuit that has an electrical problem - that is just asking for serious trouble. Don't do it!

It sounds as though a wire carrying power is touching ground somewhere. Check your new wiring to see if any of the insulation has a worn or melted spot where it might be able to touch other metal. Also check any factory wiring you may have moved or damaged while working. Never, ever run wires where they will contact or rub on a metal edge - the insulation needs additional protection from that...

Find the problem, don't just try a bigger fuse. Fuses too large for the capacity of the wires is BAD MOJO.

 

There's your problem bro.

What do you think that grommet is for, show?

It's to keep the wire off the metal so you don't get shorts, start fires, or generally turn
your car into a molten pile of charred metal and melted plastic...

 

i checked and double-checked all my wiring.... nothing looks wrong or out of place. i hope its just the new headunit that wants more juice.

 

well after reading everything above, it's clear that the specific cause of the fuse repeatedly blowing is unknown, so therefore, you 100% should*not* put a hger amp fuse in that circuit, unless you want to really screw your car up.

And under those cirsumstances, I dont think your dealer would be covering that stuff under warranty

 

The wiring is sized according to circuit load as well, so placing a larger fuse in the circuit now risks overheating the wiring. I would say you have a short somewhere (or a partial short). Try unhooking the wiring you put in and wire two sidemarkers in right off the dome. Just use some alligator hooks or similar device and run then straigt off the light with a couple of feet of wire. If everything is good then, start searching your wiring for defects.

 

What engifineer said for sure. Divide and conquer