enough fuse for running lights?

[modarch]

I have a '02 Toyota Tacoma. It has an inline blade fuse that feeds the trailer wiring harness for the running lights. It is 5 amps. Will that be enough for the 10+ lights that run off the running light circuit? I count 10 running lights, the 2 tail lights, and the license plate light.

All are incandescent except for the tail lights (which are LED). If it is too much, it will just blow the fuse, right?

[ROBERTSUNRUS]

Originally Posted by modarch

I have a '02 Toyota Tacoma. It has an inline blade fuse that feeds the trailer wiring harness for the running lights. It is 5 amps. Will that be enough for the 10+ lights that run off the running light circuit? I count 10 running lights, the 2 tail lights, and the license plate light.

All are incandescent except for the tail lights (which are LED). If it is too much, it will just blow the fuse, right?

Hi, have you tried it yet and has it blown the fuse? A five amp fuse would be fine if it just powers a relay for the trailer tow package, but if this fuse runs the lights, instead of the relay carrying the load, I would think you should have at least a ten amp fuse. Fuses are supposed to be weaker than the wires in the system and if there is a short, and the fuse is too big [amps] the wires will melt and the vehicle could catch fire. Check owner's manual to see what the correct fuse is and what it actually powers.

[Minnie's Mate]

Robertsunrus knows way more about such things than I do so I'd follow his advise first, but, my jack will run off of the umbilical if my house batteries are dead and it takes a 20 amp fuse. I have a break in the hot wire that goes to the jack motor and keep blowing fuses so I know what size it takes.

Also, there is a thread on lighting the running lights while disconnected from the tow vehicle such as having them on at the camp site for decorative purposes. In that thread the easy way to do it is to place a 20 amp blade fuse in the umbilical to bridge the hot wire from the house battery and the running lights. Having said all of this, you can put a smaller blade fuse in and it will be "safer" than a larger one in that it will blow quicker giving you an extra margin of safety, but it will also give you extra frustration because it will blow quicker.

[modarch]

Originally Posted by ROBERTSUNRUS

Hi, have you tried it yet and has it blown the fuse? A five amp fuse would be fine if it just powers a relay for the trailer tow package, but if this fuse runs the lights, instead of the relay carrying the load, I would think you should have at least a ten amp fuse. Fuses are supposed to be weaker than the wires in the system and if there is a short, and the fuse is too big [amps] the wires will melt and the vehicle could catch fire. Check owner's manual to see what the correct fuse is and what it actually powers.

I haven't tried it yet. My running lights on my Caravel are ALL in bad shape, and I have removed the bulbs in all of them and I have removed the fixtures all together up front to fix some leaks. Since I have owned the trailer I have towed it with temporary lights that were taped to the bumper! I plan on polishing this spring, so I am debating on waiting to install the new running lights until after the polish to make polishing easier. I guess when I do install the lights, I will hook the trailer up to the TV and insert bulbs one fixture at a time. If it blows, I will know that there is too much load on the 5 amp circuit.

I don't have the factory tow package, so I am pretty sure it isn't feeding a relay. My tacoma has a small black box mounted to the rear of the cab behind the back seat. It is labeled as "converter with bracket". The inline fuses feed into the box and then wires look to come out and go straight back to my factory installed 4 pin connector. From there I have installed a 7 pin connector that plugs into the factory 4 pin (I have to hard wire the 12v, brake and ground).

I guess if I have problems with the 5amp max running light circuit, I will have to buy and install a modulite or powered converter

[Silvertwinkie]

5 amps seems fairly low. I know my unit has about 13 lights on the trailer alone and I have a 20a in the fusebox of the truck.

I migrated to all LED running lights and I can use a 5amp fuse to run the trailer lights when parked (placing a 5amp into the plug, to feed the running lights from the coach batteries). If you are all incandescent, I would think you'd blow a 5 amp fuse, but give it a try and see.

My suggestion since you are doing the work already is replace the lights with LED bulbs or LED fixtures. A bit more costly than bulbs, but they will last a LONG, LONG time and take considerably less power to operate and have significantly less heat. The power consumption just can't be beat...it's about as low as you can get without turning everything off.

[modarch]

Update- I got my new running lights and new license plate light installed today. I took all but one bulb out of each clearance light fixture and connected it to my TV. Turned the headlights on and then installed the second bulb in each clearance light fixture- one at a time. I was able to get all 10 clearance light bulbs in and the after a minute or two- it blew the fuse. So I pulled the second bulb out of the 2 side clearance lights on each side, so I removed a total of 4 bulbs. Changed my 5amp fuse and turned the lights back on. That did the trick. So- if I want the full intensity at the side clearance lights I have to 1) change the side lights to LED (won't match the incandescent and very $$) or 2) get a modulite power converter. I looked at the trailer with only 1 bulb in the side clearance lights and it looked fine. I felt I needed full intensity at front and back.

[NevadaGeo]

The 12 volt bulbs inside my A/S use 1.4 amp each. I suspect they are the same type of bulb in the running lights. 1.4 times how many bulbs=

[Silvertwinkie]

The price of LED lights is a bit higher, but not totally unreasonable. I changed all my running lights to LED and when I run my lights on when totally disconnected from the tow vehicle (for campsite lighting), I can plug in a 5 amp fuse with no issues at all. If I am boondocking, the 10 lights I have could run for days and not pull nearly any power from the batteries. I am fairly sure I could run all 10 lights off a 2.5a fuse and still be ok, they draw such low, low amounts of power.

I would suggest wholeheartedly changing over the running lights and license plate light to LEDs. Besides less power draw they last much longer and, they generate significantly less heat.

[tadpoletim]

I have just bought a 2005 Classic 30 with slide and hauled it home with my 2003 Chev Silverado 3500 Duramax. We were unable to get the running/clearance lights working even after triple checking all the connector pins and terminals and have blown the LR marker fuse in the box under the hood three times. The original was a 10 amp and I tried a 15 amp with the same result. They work fine on my other trailer (horse trailer).
Can or should I try a larger fuse or is there a wiring problem in the AS trailer? The unit looks to be in excellent condition and was stored indoors for the last two years.

[TG Twinkie]

Do not increase the fuse size. Locate the problem.
Shorted light fixture is the likely culprit.

[tadpoletim]

Thanks. Any suggestions for finding the problem? Do I have to physically inspect and trace the wires back from the umbilical?

[ROBERTSUNRUS]

Originally Posted by tadpoletim

Thanks. Any suggestions for finding the problem? Do I have to physically inspect and trace the wires back from the umbilical?

Hi, try the simplest things first. I would remove all of the tail light bulbs and if that still didn't stop fuse burning, I would remove all of the marker light bulbs.

I have found in-correct bulbs installed, grounded bulbs, and bulbs where a filament has broken and connected to the other filament causing an over load condition. One bad or in-correct bulb can cause these problems. Tracing wires is quite difficult and something to do when all else fails to find the problem.

[J. Morgan]

99%+, the short is going to be near the end of the wire, either in or near the umbilical, or at or near the termination at one of the various lights.

I would start in the umbilical plug.


Superat stultitia.