PoonerElRay

The bulbs on the license plates are 5W, and there are only 10W aftermarket bulbs available.

Is it possible and safe to change the fuse for this light to a 10W so they will match the 10W aftermarket bulbs?

Will this put stress on tany of the electrical circuitry?

viper

There is some bad information here. No such thing as a 10W fuse. Fuses handle current and are rated in amps. Generally speaking it is a very bad idea to change a fuse to a higher capacity fuse. You are inviting disaster. If you have a 10A fuse protecting a circuit then this means that every device in that fused circuit can safely handle 10 amps. When this current is exceeded the fuse blows. If you put in a 20A fuse then every device in the circuit will now act as a fuse and will blow before the new fuse does.

PoonerElRay

Thanks for the reply Viper. What if all I do is use a 10W bulb in place of the stock 5W bulb? Is that dangerous to the circuitry or the fuse?

I know I'm running the risk of damaging the lens too.

viper

A 10 watt bulb will draw twice the current of a 5 watt bulb. In a 12 volt system this means .84 amps instead of .42 amps. This is not a big deal. Worst case would be the circuit is running pretty close to the 10 amp capacity of the fuse and the excess current would blow the fuse. This is highly unlikely. As for damaging the lens I don't know what you are talking about.

PoonerElRay

Viper:

So technically speaking, it's ok to use 2 10W bulbs to replace the 2 5W bulbs?

The lens meaning the transparent plastic that covers the bulbs directly above the license plate.

PoonerElRay

What I meant to say is:

If the two stock 5W bulbs are both running on a single 10amp fuse, they'll be using a total of 0.84 amps.

If the two replacement 10W bulbs are both running on a single 10amp fuse, they'll be using a total of 1.67 amps, which is beyond the threshold, correct?

How do I know if both bulbs run on the same fuse or do they have a fuse per bulb?

viper

The answer is simple. Change the bulbs. If you are technically inclined you can put an ammeter in series with the circuit to see what the nominal current drain is but why bother. If the fuse blows you have exceeded the current capacity of the circuit. No harm done and fuses are cheap.

preyx

I have already replaced my 5W bulbs (for the license plate) with 10W bulbs. No fuses have blown, and the difference in brightness is just staggering.

The only thing I'd worry about is the extra heat generated, but I installed my lights only a few weeks ago, so at least in the short term there appears to be no damage related to it (warping, etc.). As for long term, we'll have to see...

PoonerElRay

What's the longest you've driven with those 10W bulbs operating? Were the lens hot as in burning hot?

I think the lens are capable of handling them since the interior cabin light use stock 10W bulbs too, and those lens are more or the same all around the car.

viper

Don't worry about the heat. Good engineering practice is to provide spec's at least 3X what is actually necessary. It doesn't matter if you are designing bridges or radios. Over engineering is present in all but the cheapest products.

PoonerElRay

Thanks for the reassurance there Viper. I'm heading out to get some 10W Xenon-look-a-like bulbs this weekend. Will post up photos soon.

CarlssonPower

I changed the stock bulbs to the 10w bulbs. They generate too much heat so one of the lense (the transparent cover) actually "melted". Now I take off both of the lenses and just leave the bulbs there. One of my rear fog light has stop working. (My car is only one month old). I do think the incorrect wattage do damge the light system. But I couldn't find any aftermarket 5w licence bubls, they are all 10w. Should I continue to go for the look or change the stock bulbs back? .. What do you guys think?

PoonerElRay

PK Kid:

Put the lens back on because if water gets into the contacts, who knows what will happen!!!

Secondly, only one rear fog lamp is supposed to work, the left rear. That's the design.

Thirdly, try locking and unlocking your car, you won't see any flashing lights anymore because the 10W bulbs will interfere with the circuits.

For a while back, I was looking for aftermarket 5W bulbs, but those are not made. I tried everywhere. I also melted my lens and I bought a new one from MB. Now I don't care about those anymore. I have them back with original stock 5W bulbs.

Don't bother...

CarlssonPower

I thoguht I damaged the rear fog lights.. I think I'll put the stock bulbs back just to protect any possible circut problems.. Thanks for the infos. =)