Fuse blown- what's wrong?

mhchockey84

Member
Jun 27, 2011
132
NJ
Went to turn on my lights after installing them today and my grill/fog lights would t turn on. I went and checked the fuse and it was blown so I went and replaced it. Blown again so I checked my wiring at the connection point where i connected my lights and it was all good. Tried moving the wire over to another switch button blown again. I'm using a 30A in-line fuse holder and have tried using 15 20 25 v fuses


The lights are


2x linz6


2x vertex


Controlled by an AWL volunteer handheld siren


BTW it worked yesterday when I finished the install?


Any ideas?
 

Jamey@NNE

Member
Jun 23, 2011
1,661
Ocoee, Florida
Please dont keep going up in fuse size just because it blows. You will cause a fire. Check all wires after the fuse for shorts. if there are more than 1 light after the fuse disconnect them one at a time till it no longer blows to find a bad light or segment of wire.
 

tvsjr

Member
Oct 7, 2012
611
TX
mhchockey84 said:
Went to turn on my lights after installing them today and my grill/fog lights would t turn on. I went and checked the fuse and it was blown so I went and replaced it. Blown again so I checked my wiring at the connection point where i connected my lights and it was all good. Tried moving the wire over to another switch button blown again. I'm using a 30A in-line fuse holder and have tried using 15 20 25 v fuses

The fuse blows, so let's use a bigger fuse. :thumbsup:


Fuses exist to protect the wiring and whatever surrounds the wiring from thermal damage (you can read that "fire"). Fuses should be sized for 125% of the maximum expected steady-state current consumption of the load - but never bigger than what the wire (size and length) is capable of carrying. Whelen has a very nice wire gauge/amperage/length chart if you haven't seen it. In this case, your wiring isn't entirely clear... is this fuse only servicing the four lightheads, or is this the input to your siren? If it's just the 4 lightheads, 5A should be more than sufficient.


BTW, automotive fuses are sized based on amperage - so the number on top indicates 5, 10, 15, 20 amps... not volts. Your fuse holder is rated to handle, at biggest, a 30A fuse. Voltage doesn't matter in this instance since we presume you're working on a nominally 12V system... but most blade fuses are designed for 30 volts maximum.


Please - if you don't understand the basics of electronics, find someone to help you who does. Chances are there's someone on your department, a local ham radio operator, a local radio tech, someone who will gladly help you. It might cost you a few bucks, a lunch, or a case of beer (the beer should be delivered *after* the install is done, not before!). The concepts aren't hard, but you need to understand them before you damage your equipment, damage your vehicle, or wind up with your ass hanging out when you're trying to protect a scene with your lights and they fail on you. If you're going to trust your safety to this stuff, it needs to be done right.
 

mhchockey84

Member
Jun 27, 2011
132
NJ
Ok so I went back checked all my wiring and my connections seem to be good. I placed the proper size fuse in and it instantly blew, even though the controller was turned off. Is it possible that the four lights are drawing to much current and need to be separated for power ?
 

tsquale

Lifetime VIP Donor
Oct 12, 2010
10,511
Minnesota, USA
mhchockey84 said:
Ok so I went back checked all my wiring and my connections seem to be good. I placed the proper size fuse in and it instantly blew, even though the controller was turned off. Is it possible that the four lights are drawing to much current and need to be separated for power ?

If it blew even with the controller off, there is still power getting through to it somewhere. I would disconnect all power to your controller and lights and have someone with more electrical experience check things out, if not rewire it for you.
 

tvsjr

Member
Oct 7, 2012
611
TX
mhchockey84 said:
Ok so I went back checked all my wiring and my connections seem to be good. I placed the proper size fuse in and it instantly blew, even though the controller was turned off. Is it possible that the four lights are drawing to much current and need to be separated for power ?

Those four lights should draw at the *absolute* worst 5 amps. You need to find someone with more electrical skills to review your wiring... or, if you want help via Internet forum, you need to provide a very detailed description of the entire wiring path (from the controller, to the lights, to ground). Pictures help too.
 

Andy L.

Member
Jun 16, 2010
282
Michigan
When you say grill/fog lights do you mean just the placement of the LINZ6 and Vertex or do the fog lights not work too?


Like the others said, with the switch off there should be no power in the system so if the fuse is blowing you have yourself a wiring problem. Things aren't hooked up correctly.
 
May 24, 2010
1,627
PG County, MD
mhchockey84 said:
Ok so I went back checked all my wiring and my connections seem to be good. I placed the proper size fuse in and it instantly blew, even though the controller was turned off. Is it possible that the four lights are drawing to much current and need to be separated for power ?

Did you visually inspect all of the wiring, and by that I mean hand over hand run it down from light heads to fuse?


Is it loomed or laid out bare? If it's bare, after you find your problem, loom it.


How does it get into the cab, firewall, through the door hinge (I hope not), how? Is there a grommet in the hole it goes through?


Where are the light heads grounded to?
 

Q2bman

Member
Jan 27, 2012
116
USA oklahoma
Check you 12v connections with a meter on the continuity setting. Touch one probe to ground and one on you 12v switched source. Track it to your short. It is a short. Something is wired wrong. If you keep trying it by blowing fuses you will screw up your lights. My buddy went through a pile of fuses to find a pinched wire to ground under a flange. He fixed it only to find he fried the ability for his interior lightbar to change patterns. All whelen stuff! Be carefully. Mentioned before, you could melt a wire and cause a fire or damage sensitive circuitry.
 

mhchockey84

Member
Jun 27, 2011
132
NJ
From my lights I have a 12g wire to the inline fuse but the wire coming from the controller that goes into the other end of the fuse . Is a smaller wire could my fuse be blowing because the smaller wire can't handle the load?
 

Andy L.

Member
Jun 16, 2010
282
Michigan
You said the fuse is blowing instantly with the switch off correct?


How are the lights wired?

  1. All the red (read as power wire if you have different colored LED) wires hook together and then to your 12ga power wire?
  2. All the black wires connected to a nearby ground, or run to a central grounding point?
  3. Grey sync wires connected to each other and nothing else?
  4. White/purple are either unconnected or connected to momentary power source?
 

mhchockey84

Member
Jun 27, 2011
132
NJ
Andy L. said:
You said the fuse is blowing instantly with the switch off correct?

How are the lights wired?

  1. All the red (read as power wire if you have different colored LED) wires hook together and then to your 12ga power wire?
  2. All the black wires connected to a nearby ground, or run to a central grounding point?
  3. Grey sync wires connected to each other and nothing else?
  4. White/purple are either unconnected or connected to momentary power source?

Yes I tried running a new power line and again as soon as I connected the wire to the control box (powered off) the fuse instantly blew
 

rescue52

Member
May 23, 2010
386
New York
With the fuse out, what happens when you place a circuit tested in the fuse holder?
 

fire1

Member
Jun 5, 2011
621
Michigan
mhchockey84 said:
Yes I tried running a new power line and again as soon as I connected the wire to the control box (powered off) the fuse instantly blew

Disconnect all your lights from the control box. Put a 5 amp Fuse on a separate hot from the battery. Make sure that you have a good ground. Take each of your lights, one at a time and connect to hot. If your fuse blows, you found the light that is causing the problem and you need to check your wiring very carefully. Test all lights to make sure you do not have more than one causing a problem. Also make sure that your sync & your pattern wires are disconnected on each light. After testing each light & If nothing is found, Then connect 2 lights at a time to your box, if that is OK then add the sync wire then test, if OK, then add the flash pattern wire, if OK. Then add the next 2 lights the same way. If you connect the lights to the box and your fuse blows, the problem is the box.
 

ERM

Member
May 22, 2010
720
Omaha, NE
mhchockey84 said:
Yes I tried running a new power line and again as soon as I connected the wire to the control box (powered off) the fuse instantly blew

OK. Stop everything you are doing. Do not test wires or fuses until you do this. You came to the board for help and have yet to answer the question about your layout. YOU are OUR eyes. We need you to describe exactly how your wires are laid out. From the power source to your lights, describe in detail how your wire leaves your power source, its route of travel, through which walls or channels you have run your wires and how it enters your control box (including wire color on the control box). From there, describe how your wires exit the control box (wire color) and the route to your lights and how they are wired.


Pretend you did a successful install and you are talking on the phone to your friend who has an identical vehicle and are explaining to him how and where to run his wires. What you think might be a minute detail, might be a huge no no. We can suggest everything under the sun, but without this layout, you're just voiding your warranties and risking a fire.


Tony
 

efdny2003

Member
Apr 18, 2011
388
united states, ny
The diagram is a step in the right direction, but I agree it would be ten fold easier to see pictures of the actual wiring/connection points. It probably sounds like we're all being PITAs but we're just trying to prevent any serious damage to you, your car, or your equipment. One thing I'm noticing in your diagram is it looks like you have two separate power feeds running to the Python, is that a mis-drawing or is that correct.
 

mhchockey84

Member
Jun 27, 2011
132
NJ
efdny2003 said:
The diagram is a step in the right direction, but I agree it would be ten fold easier to see pictures of the actual wiring/connection points. It probably sounds like we're all being PITAs but we're just trying to prevent any serious damage to you, your car, or your equipment. One thing I'm noticing in your diagram is it looks like you have two separate power feeds running to the Python, is that a mis-drawing or is that correct.

With the python there is a red(power) black(ground) brown(turns unit on)
 

rescue52

Member
May 23, 2010
386
New York
mhchockey84 said:
Sorry here is a diagram

How did you go through the firewall?
 

rescue52

Member
May 23, 2010
386
New York
Do the other light or siren work??


Where is the fuse that keep blowing??
 

Jarred J.

Lifetime VIP Donor
May 21, 2010
11,580
Shelbyville, TN
all lights should be grounded as close to the frame as possible. running all grounds to one place is not good. (especialy if the ground wire is longer than the power wire.)
 

ERM

Member
May 22, 2010
720
Omaha, NE
mhchockey84 said:
Sorry here is a diagram

You've drawn no fuses and indicated nothing as far as colors going into and out of the controller. You've grouped power and ground wires together in your diagram. This is not what I meant by being our eyes. Everyone is throwing suggestions at you because there are no descriptions, just generalizations. Everyone is so willing to help, you just need to provide accurate depictions. So much time and typing could be saved if you just described exactly what you did.
 
Sep 13, 2010
761
Holland, Michigan
I had a similar problem before with snow plow wiring. I pulled everything out and inspected every inch of every wire in the harness. I found 1 little nick in the wiring on one wire. It rubbed up against something somewhere and was causing a short. I ended up making a whole new harness because I didn't like the design of the old one anyway. You will be doing youself a favor by pulling everything out and making a new one. Installing all new wire into wire loom and re-installing the new harness. It will look cleaner and will be protected by the loom.
 

mhchockey84

Member
Jun 27, 2011
132
NJ
rescue52 said:
Do the other light or siren work??

Where is the fuse that keep blowing??

Yes the other talon and python work no problem and the siren works.


The fuse is an inline fuse inside the vehicle .

hitman38367 said:
Why are there two positive leads coming from the battery to the control box?

There are 2 positive leads because the controller takes 2 positive one for the siren and another for the lighting controller part to power the lights
 

mhchockey84

Member
Jun 27, 2011
132
NJ
Marked where the fuses are


CORRECTION TO MY PAINT POST THE INLINE FUSE IS IN THE VEHICLE AFTER THE WIRE PASSES THROUGH THE FIRE WALL


and i will post wiring pictures once i get home and the rain slows down

carright.jpg

elight.png
 
Last edited by a moderator:

hitman38367

Member
May 23, 2010
881
West Tennessee, USA
mhchockey84 said:
Yes the other talon and python work no problem and the siren works.
The fuse is an inline fuse inside the vehicle.
If everything else works except that one circuit then you have a massive short in that individual circuit. You are going to have to inspect every connection, inch of wire, terminal ending, and length of run for that circuit and those individual lights. You may even have to look inside the control box to make sure you don't have a cross connection or something that is feeding too much power to that circuit. I am of the same mind as ERM. I need pics, descriptions, wire sizes, etc. to help make a determination on what's going on.
 

Jarred J.

Lifetime VIP Donor
May 21, 2010
11,580
Shelbyville, TN
no fuses on power but one on ground? FAIL!
 

ERM

Member
May 22, 2010
720
Omaha, NE
mhchockey84 said:
Marked where the fuses are

For generalized assistance, use a light tester at the fuse point. This tester looks like an ice pick with a clear handle and a wire coming out of the end of it. Connect the alligator clip to a positive source and probe the terminal of the fuse holder that exits to the lights. If the tester lights, you have a ground signal present on this wire when you shouldn't. Next, sever the connection of this wire at the "centralized location" and retest the fuse holder. If it lights again, you have a cut in the wire somewhere between the fuse point and your lights. If it doesn't light, you have a problem in your centralized location.


Disconnect each light, replace the fuse and test each lighthead to make sure there is not a problem with a particular lighthead. If all lightheads are working, turn off the circuit, reconnect everything and turn it back on.


Not understanding your above post with new picture. Is your inline fuse inside the cabin or in the engine compartment. There should be a fuse as the controller's wire comes off the battery, then passes through the firewall and into your controller. The output should have an inline fuse as it exits the controller and before it goes through the firewall.
 

mhchockey84

Member
Jun 27, 2011
132
NJ
ERM said:
For generalized assistance, use a light tester at the fuse point. This tester looks like an ice pick with a clear handle and a wire coming out of the end of it. Connect the alligator clip to a positive source and probe the terminal of the fuse holder that exits to the lights. If the tester lights, you have a ground signal present on this wire when you shouldn't. Next, sever the connection of this wire at the "centralized location" and retest the fuse holder. If it lights again, you have a cut in the wire somewhere between the fuse point and your lights. If it doesn't light, you have a problem in your centralized location.

Disconnect each light, replace the fuse and test each lighthead to make sure there is not a problem with a particular lighthead. If all lightheads are working, turn off the circuit, reconnect everything and turn it back on.


Not understanding your above post with new picture. Is your inline fuse inside the cabin or in the engine compartment. There should be a fuse as the controller's wire comes off the battery, then passes through the firewall and into your controller. The output should have an inline fuse as it exits the controller and before it goes through the firewall.

the inline fuse for the problem lights is after the firewall inside the cabin
 

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