Fuses needed when adding to existing lights?

[Donner]

Sorry, just don't know, but if you add a set of back up lights to the vehicle; and the vehicle's reverse lights were spliced to accommodate the new lights, would a new fuse be needed?

The stock is 7.5. It blows every time lights get hooked up. I tested a 20 amp fuse and no problem. Is this recommended? Danger?

Thanks!

 

[Turdle]

Sorry, just don't know, but if you add a set of back up lights to the vehicle; and the vehicle's reverse lights were spliced to accommodate the new lights, would a new fuse be needed?

The stock is 7.5. It blows every time lights get hooked up. I tested a 20 amp fuse and no problem. Is this recommended? Danger?

Thanks!

Nooooo!
stop right there--

You need to run a new 12 volt source wire back there, preferably right off the battery. You might want to consider getting a power block.This lead should be fused within 18" of the battery.
You then connect a relay to the "existing" light wire, using it for a "trigger" to switch the relay on.

Then, the new power wire is connected to another pin on the relay-and the power lead from the "new" light(s) to yet another relay pin.

the light(s) circuit is then grounded, as is the relay.

You should be able to google a relay schematic.

Never increase the value of an existing fuse!!!!!!!

 

[Donner]

ut oh... So how did it work before, and now it's blowing fuses? The back up lights are connected to the same wiring that a kit was installed to.

I"ll be back... I need to replace a fuse. Thanks!

 

[Turdle]

Never increase the fuse value in the stock fuse panel!!!!

That is what auxiliary panels are for.

 

[Dannyboy]

Just a suggestion, I added a block like JTsmith mentioned with a writeup here

http://www.explorerforum.com/forums/showthread.php?t=202857&highlight=aux+fuse+panel

Gathering a good understanding of respecting tolerences of wires, switches etc will make you learn really quick that you cannot overload a fuse because typically a wire or most often a switch is the weakest link and will burn up.

 

[Donner]

Thanks guys! It's back to 7.5. I disconnected the power from the lights also.

 

[Sandy]

As jts has stated, just add an Automotive Relay under the hood rated at 30 amps.
Run a fused power wire from the battery to pin 30 on the Relay, from pin 87 run another wire to the lights at the rear of the vehicle.
You can use the existing wire to activate the relay using pins 85 and 86 or you can add a switch to do it too.

If the wattage of the lights is 55 x2 or 110 watts the amperage draw will be a little less than 10 amps so 14 gauge wire will probably do OK, a larger gauge wire will work also.
This amperage also applies to the Fused Line from the battery to pin 30 on the relay, use a 20 amp fuse if using 14 or 12 gauge wire. If you go larger than 20 amps on the fuse consider using larger gauge wire say 10 gauge.
If the backup lights are all that will be run off of the circuit then 20 amps should be enough.

The switch wire for the relay can be 16 or 18 gauge.

 

[Blacksheep Josh]

Never increase the value of an existing fuse!!!!!!!

Haha, I'll be right back, I got 2 or 3 I need to switch out then. I've been wondering what that smell was..... lol j/k

 

[aldive]

My aux backup lights were simply spliced intothe existing circuit. I did not add or change any fuse.

Been working perfectly for 9 years.

NOTE: NOT RECOMMENDED This has worked well for me but its not the correct way to do it.

 

[Blacksheep Josh]

I just thought of this to, what about using l.e.d.? I'm sure you coudl fab up something that gives off enough lights, and because they draw such low power maybe you wouldn't need to do anything extra concerning the wiring or fuses that are all ready in place. Just splice into it like you are now.

 

[Rick]

My aux backup lights were simply spliced intothe existing circuit. I did not add or change any fuse.

Been working perfectly for 9 years.

Lucky guy.

Why pass on that info to folks making them think it's ok, unless you know their auxiliary lights draw as little, or less current than yours? Sure would suck to burn up a wiring harness. When the insulation melts on that reverse light wire, it will melt through the insulation of the surrounding wires as well making for all sorts of fun...

 

[aldive]

Gee Rick, 9 years is a pretty good record.

 

[Donner]

Just happen to have a 30amp relay

As jts has stated, just add an Automotive Relay under the hood rated at 30 amps.
Run a fused power wire from the battery to pin 30 on the Relay, from pin 87 run another wire to the lights at the rear of the vehicle.
You can use the existing wire to activate the relay using pins 85 and 86 or you can add a switch to do it too.

If the wattage of the lights is 55 x2 or 110 watts the amperage draw will be a little less than 10 amps so 14 gauge wire will probably do OK, a larger gauge wire will work also.
This amperage also applies to the Fused Line from the battery to pin 30 on the relay, use a 20 amp fuse if using 14 or 12 gauge wire. If you go larger than 20 amps on the fuse consider using larger gauge wire say 10 gauge.
If the backup lights are all that will be run off of the circuit then 20 amps should be enough.

The switch wire for the relay can be 16 or 18 gauge.

Thank you! I'll try this right now...

 

[Rick]

Gee Rick, 9 years is a pretty good record.

Yes, for you and your lights. As I've already said, unless you know everyone else is going to run the same or less current draw, it's a bad idea to promote your setup. There is a good reason most auxiliary lighting kits come with their own relays

I just looked up a set of PIAA backup lights. They pull 4.5A each... That's 9 amps for just the auxiliaries, then add whatever the stock lamps draw. Just a bit overloaded on a 7.5a circuit and those are "dedicated" backup lights. Many of us who use our Explorers offroad use even more powerful lamps.

 

[Dannyboy]

I can agree with Rick here, I burned up a factory headlight switch in a matter of 2 weeks running aftermarket fog lights in my factory fog light location on my 94.

They didn't look too much different than this.

care to share the wattage on the bulbs.

 

[aldive]

35w x 2

 

[aldive]

Yes, for you and your lights. As I've already said, unless you know everyone else is going to run the same or less current draw, it's a bad idea to promote your setup. There is a good reason most auxiliary lighting kits come with their own relays

I just looked up a set of PIAA backup lights. They pull 4.5A each... That's 9 amps for just the auxiliaries, then add whatever the stock lamps draw. Just a bit overloaded on a 7.5a circuit and those are "dedicated" backup lights. Many of us who use our Explorers offroad use even more powerful lamps.

I edited my post saying its not recommended.

 

[Donner]

Questions...

My aux backup lights were simply spliced intothe existing circuit. I did not add or change any fuse.

Been working perfectly for 9 years.

NOTE: NOT RECOMMENDED This has worked well for me but its not the correct way to do it.

Lucky guy.

Why pass on that info to folks making them think it's ok, unless you know their auxiliary lights draw as little, or less current than yours? Sure would suck to burn up a wiring harness. When the insulation melts on that reverse light wire, it will melt through the insulation of the surrounding wires as well making for all sorts of fun...

I had three companies do the same thing - splice into the reverse wiring - low watt bulbs except the last one (55x2, which I was trying to replace). Can reverse light wiring burn up that fast considering the short time it's used? Or is it burning while the engine/motor is running?

 

[Bill Kemp]

When the lights are ON is the only time they will put a draw on the elect. system.
However if a melt down is started it will only continue to get worse each time you put it in reverse.
55 watt bulbs should be run thru a relay no matter where they are.
As mentioned before, a set of LED lights may do as well with no relay. Although I dont know of any very bright LED fog/back-up type lights.

 

[Donner]

Got it...

As jts has stated, just add an Automotive Relay under the hood rated at 30 amps.
Run a fused power wire from the battery to pin 30 on the Relay, from pin 87 run another wire to the lights at the rear of the vehicle.
You can use the existing wire to activate the relay using pins 85 and 86 or you can add a switch to do it too.

If the wattage of the lights is 55 x2 or 110 watts the amperage draw will be a little less than 10 amps so 14 gauge wire will probably do OK, a larger gauge wire will work also.
This amperage also applies to the Fused Line from the battery to pin 30 on the relay, use a 20 amp fuse if using 14 or 12 gauge wire. If you go larger than 20 amps on the fuse consider using larger gauge wire say 10 gauge.
If the backup lights are all that will be run off of the circuit then 20 amps should be enough.

The switch wire for the relay can be 16 or 18 gauge.

I'll see how this works...