why is my fuse kept BLOWING?

[gonefishie]

Are any of you guys using this type of converter from Draw-Tite and have any problem?<br /><br />

<br /><br />Well my problem is that the fuse that is in-line with the power wire connected directly to the battery keep blowing after about an hour of usage WITH THE RUNNING LIGHT ON. Without running light it works forever. I'm not new to trailer light problems and have checked all the ground and wires, bulb sockets, etc.. Do you think it could be that the converter is going bad and blowed the fuse when it gets hot? or have I not checked my running light wire throughly enough? If it's a problem with the running light circuit how come it took an hour for the fuse to blow instead of immediately?

 

[Silvertip]

Re: why is my fuse kept BLOWING?

Electrical circuits are protected by fuses rated to open (blow) when a specific amount of current passes through them. A 10 amp fuse for example will blow when 10 or more amps passes through it. In your case, the fuse may not be big enough to handle the extra lights. You are adding at least seven (two tail and two side marker, and three rear marker lights). Although this isn't a great deal of current it may be enough to gradually heat up the fuse to the point where it eventually blows. What size fuse is blowing? Is that what the converter manufacturer recommends.

 

[gonefishie]

Re: why is my fuse kept BLOWING?

The blown fuses are 10A and it came with the package. On the fuse holder it does says 15A max. I went ahead and put in an 15A fuse but haven't had the chance to test it.

 

[Silvertip]

Re: why is my fuse kept BLOWING?

The 15 amp maximum rating is related to the construction of the fuse holder and the size (gauge) of the wire into and out of it. If the 15A fuse blows, there is definitely a problem with the converter. What type of vehicle is this converter installed on?

 

[gonefishie]

Re: why is my fuse kept BLOWING?

Well I spoke to tech support and they said that I might have an overload problem. 2 set of stop/turn/running lights (all in the same box). 3 clearance lights, and 4 side markers. They suggested that I should upgrades to an heavy duty version ModuliteHD which would be able to handle up to an 20A load. What confused me is how come it has been working fine for the past 10 months? Something somewhere is causing an additional current draw. I have a 2002 Tundra by the way. I'm going to find out how much the trailer is drawing.

 

[byacey]

Re: why is my fuse kept BLOWING?

Measure the current and one by one remove the light bulbs from the running lights. This will tell you how much each bulb is drawing and will indicate if there is one drawing an unusual amount of current. The sum of each bulb should add up to the total current draw. Example : If each bulb draws 400ma = .40A, and you have 6 bulbs the total current should be 2.4A. With all the bulbs removed there should be zero current. If there is still current look for corrosion in sockets or damaged / corroded wiring.

 

[Mark42]

Re: why is my fuse kept BLOWING?

Not knowing the bulb sizes, I calculate 110 watts of lights using the 35w stop/tail/turn and 5w each running light. That puts you at 9.1 amps. Too close for comfort. <br /><br />I suggest that instead of replacing the converter, to switch to LED lights that pull in the ma range. It will take a heck of a lot of LED's to pull one full amp. <br /><br />Another issue could be you have a short in the running light harness. It is common to have a worn wire that only shorts when a big bump is hit, or the frame twists just so. <br /><br />At any rate, it looks like you have some homework to do.

 

[ZR8RIDER]

Re: why is my fuse kept BLOWING?

I'm not sure if this will help. I think you are overloaded also. I bought an in line circuit breaker from draw-tite. It plugs right in between your vehicle and the trailer. Use it whenever towing. If there's a problem the leds go from green to red. No more blown fuses. You still need to figure out your problem, but this makes things easier.