I have replaced my horn/tailight fuse 3 times already this year. It just keeps on blowin for some reason. Does anyone know how to fix this or maybe an idea on how to diagnose this? Thanks in advance!
Need HELP! Horn/Tailight fuse keeps blowin'
- Thread starter jagtiger
- Start date
Fuse 45 feeds or is connected to lots of stuff so trouble shooting here will be hard. Is the fuse blowing related to any recent changes to the electrical system. Does it blow when you step on the brakes, blow the horn or when it's raining out. Do you have a stick or auto trans. Are you installing the right size fuse, it should be a 20A.
I had the same problem to. Reason why is because I am running an aftermarket horn which I think requires a 30a fuse 
Not only would my fuse for the horn/rear tail light blow but I had to use my key to enagage my shifter on my auto tranny 
Well, I changed the fuse to a 30A fuse and I haven't had any problems thus far.
Not only would my fuse for the horn/rear tail light blow but I had to use my key to enagage my shifter on my auto tranny Well, I changed the fuse to a 30A fuse and I haven't had any problems thus far.
I would never recommend going to a larger fuse. Fuses are sized to supply the load and more importantly protect the wiring from being damaged (melting and burning). In 1TITENSX situation I would install a relay to switch power from another source for the horn.
Yellow Rose
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- 22 November 2001
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Check Your Wire
The fuse for the third tail light is the same for the horn.
Open your trunk. Look at the left strut and you will see a black wire that disappears into the trunk lid panel, which goes to the brake light on the spoiler.
Over the years of opening and closing the trunk, my wire actually broke in half. When it did the circuit shorted and blew the fuse. I repaired the wire and replaced the fuse with no problems since.
The fuse for the third tail light is the same for the horn.
Open your trunk. Look at the left strut and you will see a black wire that disappears into the trunk lid panel, which goes to the brake light on the spoiler.
Over the years of opening and closing the trunk, my wire actually broke in half. When it did the circuit shorted and blew the fuse. I repaired the wire and replaced the fuse with no problems since.
Hi Folks! Thanks for the replies - It's actually the brake lights/horn fuse that's keep on blowin and not the tail lights.
Briank ,
- It's been like this when I bought the car last year. Previous owner has installed a aftermarket 2 ch amp for the stereo. Its a manual Trans.
Ititensx,
I'm not sure if using a 30a fuse will work or do more damage later on?
AndyVecsy,
I will try and check that black wire running thru the trunk - Hopefully I got the same problem as yours. Thanks a lot!
Briank ,
- It's been like this when I bought the car last year. Previous owner has installed a aftermarket 2 ch amp for the stereo. Its a manual Trans.
Ititensx,
I'm not sure if using a 30a fuse will work or do more damage later on?
AndyVecsy,
I will try and check that black wire running thru the trunk - Hopefully I got the same problem as yours. Thanks a lot!
Jagtiger, did you ever find a solution? I'm having the same trouble. Can't find a pattern to why the fuse trips, so it sounds like it might be a bad wire.
Yes...I replaced the fuse with the the higher amp rating. Never have the problem again...I can't remember if it's 20amp or 30 amp..I'll check it out when I get a chance.
thedon67 said:
Bringing back to life.....this started happening to me today...well I have no idea how long since I dont usually use the horn and cant see if my brake lights go on....
Last thing I did was change the oil which I've done numerous times, doubt this would have anything todo with it..just blew 2 extra 20a fuses..
I want to take the easy fix of installing a 30a fuse, seems like its been fixing the issue. any drawbacks to this???
Last thing I did was change the oil which I've done numerous times, doubt this would have anything todo with it..just blew 2 extra 20a fuses..
I want to take the easy fix of installing a 30a fuse, seems like its been fixing the issue. any drawbacks to this???
There's always some margin of safety built into the system. Obviously the 30A fuse is working fine for Jagtiger, but there is a greater risk of burning/melting things [fire?] as BrianK stated. The circuit is tied to the brake lights, horns, cruise control and security system. Best to spend a couple hours with an ammeter and figure out the root cause IMHO.
The drawback is that the wire may burn in the wire harness somewhere. When this happens, good luck in locating the faulty broken wire. Not fun.:frown:
Danger, 30 amps is a lot more than 20 amps. I'd rather take my car out of commission and fix the problem than to have wires burn up and have to fix the damage that it causes. Your car needs an electrical diagnosis, maybe your brake light wire or horn wires are shorted out. I would check the brake light as it's in the trunk and because the lid goes up and down, the wires are subject to movement and your wires could get split open over the years and short out. Horns are usually a pretty solid and undisturbed connection unless you been messing around under the hood.
Power dissipated in the wiring is IxIxR, where I = current & r = the resistance of the wiring. So, if you go from 20a to 30a, that's 9/4 or 2.25 times the designed power for the wiring.
I don't know about you, but I would consider my wiring harness to be a rather expensive way to make toast. Measure the current through the fuse and track down the problem.
Also, are you using OEM quality fuses? A cheap fuse could blow at a steady current drain close to the 20a rating.
Frank
'96 NSX-T, red/tan
I don't know about you, but I would consider my wiring harness to be a rather expensive way to make toast. Measure the current through the fuse and track down the problem.
Also, are you using OEM quality fuses? A cheap fuse could blow at a steady current drain close to the 20a rating.
Frank
'96 NSX-T, red/tan
Re: Check Your Wire
thanks for the info regarding the 30a fuse. I will not be going this route, however thanks to this forum again, I think I found the problem just like above. My wire is crimped REAL BAD and I noticed that my spoiler brake light is not working.
Kinda worked with it and checked it out and it practically fell apart. Temporarliy spliced and attached a wire, stepped on the brake and the brake light went on.
Hopefully this would cause the fuse to blow 2 times in a row and is a quick fix...? anyone know the gauge on this wire as well , 14 or 16?
thanks
thanks for the info regarding the 30a fuse. I will not be going this route, however thanks to this forum again, I think I found the problem just like above. My wire is crimped REAL BAD and I noticed that my spoiler brake light is not working.
Kinda worked with it and checked it out and it practically fell apart. Temporarliy spliced and attached a wire, stepped on the brake and the brake light went on.
Hopefully this would cause the fuse to blow 2 times in a row and is a quick fix...? anyone know the gauge on this wire as well , 14 or 16?
thanks
Re: Check Your Wire
16 gauge will suffice for the brake light. 14 gauge will be an overkill.
16 gauge will suffice for the brake light. 14 gauge will be an overkill.
I had this problem and and the result was a bad horn. The resistance went down to zero, DEAD SHORT, on one horn, near zero on another, and in normal range for the third.
Removed the bad horns, fuse now does not blow. Ordering new ones now
Removed the bad horns, fuse now does not blow. Ordering new ones now
Im pretty sure its my cable that goes to the spoiler brake light for now.
It snapped literally in my hands and looked corroded together the green wire and black wire.
I need to drive the car in the next day or so, going to leave the brake light disconnected for now, pop a fuse back in and hopefully no blowing. This will us for sure if its the brake light and hopefully nothing else.
Thanks for all the replies- seems to be a common problem here over the years.
It snapped literally in my hands and looked corroded together the green wire and black wire.
I need to drive the car in the next day or so, going to leave the brake light disconnected for now, pop a fuse back in and hopefully no blowing. This will us for sure if its the brake light and hopefully nothing else.
Thanks for all the replies- seems to be a common problem here over the years.
I hope you're disconnecting *just* the spoiler brake lamp.
Have heard of this in the UK.
Fault was dodgy bulbs, they were just not right and kept blowing fuses.
New bulbs problem sorted.
Fault was dodgy bulbs, they were just not right and kept blowing fuses.
New bulbs problem sorted.
This is exactly the situation I had on a 1991. Replaced all horns, all is well.
On this car the fuse would blow after the horn was depressed while the brake was applied
, just put the current over the top and blew the 20 amp fuse.BTW, the NSX I am refering to is thedon67's, above in post #7.
HTH,
LarryB
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