Wiring for Third Light on Leer Cap and dome light
Wiring for Third Light on Leer Cap and dome light
Hey guys,
Have a 2010 Ranger Sport 4x4, 4.0...
Just got a used Leer cap, so installed myself.
Has the dome light (with a built in switch) and the rear brake light mounted against the interior of the glass. All wires are there, but obviously stops at the plug where I need to connect to my brake lights for 3rd light and to a power source for my dome.
First off, the brake light. From reading I've done, I cannot just tap into the trailer brake lights or onto my factory taillights, as my 3rd will blink when I activate the turn signals. Also from my reading, many say that there is a "green wire" located either the connector near my spare tire or under the hood off the master cylinder that is factory installed, but capped and is strictly for a third light. I can't find this, even after 2 hours of frustrated searching.
Does the 2010 Rangers even have this, or was this discontinued?
Any other suggestions would be much appreciated.
Secondly, I need power for the dome light. Seems simple enough...run a wire up to the battery, including an inline fuse.
Any other ideas rather than running a wire the whole way up?
Much appreciated! Thanks RFers!
Have a 2010 Ranger Sport 4x4, 4.0...
Just got a used Leer cap, so installed myself.
Has the dome light (with a built in switch) and the rear brake light mounted against the interior of the glass. All wires are there, but obviously stops at the plug where I need to connect to my brake lights for 3rd light and to a power source for my dome.
First off, the brake light. From reading I've done, I cannot just tap into the trailer brake lights or onto my factory taillights, as my 3rd will blink when I activate the turn signals. Also from my reading, many say that there is a "green wire" located either the connector near my spare tire or under the hood off the master cylinder that is factory installed, but capped and is strictly for a third light. I can't find this, even after 2 hours of frustrated searching.
Does the 2010 Rangers even have this, or was this discontinued?
Any other suggestions would be much appreciated.
Secondly, I need power for the dome light. Seems simple enough...run a wire up to the battery, including an inline fuse.
Any other ideas rather than running a wire the whole way up?
Much appreciated! Thanks RFers!
Yes, that's true about high brake light flashing with the 1 bulb rear light system.
On the Brake pedal switch you will find a Violet/white stripe wire, this wire powers the 3rd brake light at the top rear of the cab, you need to splice to that and I would add a 5amp inline fuse since the wire will be quite long and under the truck.
For the rear Dome light you really want to power that from a Battery Saver relay source.
Battery Saver Relay cuts power to most system after 20-30minutes of key off/out and doors being closed, so it does what it says, "saves the battery" if you leave something on.
I don't have a battery saver relay in my '94 and I have left my rear dome light on before, engine barely started the next morning, lol.
Fuse #11 or Fuse #13 in Smart Junction box are both for interior lights.
Smart Junction Box is in passenger side kick panel.
Glove box light would also be a source, I believe it has power all the time not just with key on, and it would for sure be one of the things battery saver relay would cut power to.
Fuse this wire as well
Don't know about the Green wire?
And use a connector at the bed level so you can take canopy off, remember to cover/seal that connector is it can short or be damaged by weather when canopy is off
On the Brake pedal switch you will find a Violet/white stripe wire, this wire powers the 3rd brake light at the top rear of the cab, you need to splice to that and I would add a 5amp inline fuse since the wire will be quite long and under the truck.
For the rear Dome light you really want to power that from a Battery Saver relay source.
Battery Saver Relay cuts power to most system after 20-30minutes of key off/out and doors being closed, so it does what it says, "saves the battery" if you leave something on.
I don't have a battery saver relay in my '94 and I have left my rear dome light on before, engine barely started the next morning, lol.
Fuse #11 or Fuse #13 in Smart Junction box are both for interior lights.
Smart Junction Box is in passenger side kick panel.
Glove box light would also be a source, I believe it has power all the time not just with key on, and it would for sure be one of the things battery saver relay would cut power to.
Fuse this wire as well
Don't know about the Green wire?
And use a connector at the bed level so you can take canopy off, remember to cover/seal that connector is it can short or be damaged by weather when canopy is off
Last edited by RonD; Dec 10, 2015 at 09:12 PM.
Something you could do is take your third brake light off and add a wire into the brake light's hot lead. Run that wire down, out and to the new one. I'd consider that to be more direct.
As for the dome, if you don't have a plan, I'd have a hot lead from either one of the cigar sockets or on it's own inline fuse from the battery but with a relay controlled by the battery saver circuit so if you forget about it, the relay will turn off after 40 minutes or so.
As for the dome, if you don't have a plan, I'd have a hot lead from either one of the cigar sockets or on it's own inline fuse from the battery but with a relay controlled by the battery saver circuit so if you forget about it, the relay will turn off after 40 minutes or so.
Yes, that's true about high brake light flashing with the 1 bulb rear light system.
On the Brake pedal switch you will find a Violet/white stripe wire, this wire powers the 3rd brake light at the top rear of the cab, you need to splice to that and I would add a 5amp inline fuse since the wire will be quite long and under the truck.
For the rear Dome light you really want to power that from a Battery Saver relay source.
Battery Saver Relay cuts power to most system after 20-30minutes of key off/out and doors being closed, so it does what it says, "saves the battery" if you leave something on.
I don't have a battery saver relay in my '94 and I have left my rear dome light on before, engine barely started the next morning, lol.
Fuse #11 or Fuse #13 in Smart Junction box are both for interior lights.
Smart Junction Box is in passenger side kick panel.
Glove box light would also be a source, I believe it has power all the time not just with key on, and it would for sure be one of the things battery saver relay would cut power to.
Fuse this wire as well
Don't know about the Green wire?
And use a connector at the bed level so you can take canopy off, remember to cover/seal that connector is it can short or be damaged by weather when canopy is off
On the Brake pedal switch you will find a Violet/white stripe wire, this wire powers the 3rd brake light at the top rear of the cab, you need to splice to that and I would add a 5amp inline fuse since the wire will be quite long and under the truck.
For the rear Dome light you really want to power that from a Battery Saver relay source.
Battery Saver Relay cuts power to most system after 20-30minutes of key off/out and doors being closed, so it does what it says, "saves the battery" if you leave something on.
I don't have a battery saver relay in my '94 and I have left my rear dome light on before, engine barely started the next morning, lol.
Fuse #11 or Fuse #13 in Smart Junction box are both for interior lights.
Smart Junction Box is in passenger side kick panel.
Glove box light would also be a source, I believe it has power all the time not just with key on, and it would for sure be one of the things battery saver relay would cut power to.
Fuse this wire as well
Don't know about the Green wire?
And use a connector at the bed level so you can take canopy off, remember to cover/seal that connector is it can short or be damaged by weather when canopy is off
Will update over the weekend.
Again, much appreciated.
Something you could do is take your third brake light off and add a wire into the brake light's hot lead. Run that wire down, out and to the new one. I'd consider that to be more direct.
As for the dome, if you don't have a plan, I'd have a hot lead from either one of the cigar sockets or on it's own inline fuse from the battery but with a relay controlled by the battery saver circuit so if you forget about it, the relay will turn off after 40 minutes or so.
As for the dome, if you don't have a plan, I'd have a hot lead from either one of the cigar sockets or on it's own inline fuse from the battery but with a relay controlled by the battery saver circuit so if you forget about it, the relay will turn off after 40 minutes or so.
Thanks for the ideas!
Thanks for the advice, RonD. Curious about the violet-white wire off the brake switch. I have found it but wonder if this is the best place to splice to the wire, or does the wire eun somewhere in the truck and is capped, or is powering something else? Where would you recommend I tap into this?
Will update over the weekend.
Again, much appreciated.
Will update over the weekend.
Again, much appreciated.
I installed aftermarket tail lights in my truck a long time ago.. so basically I have a "brake only" bulb.. the standard "brake/turn" bulb and the reverse lights in the rear.
Point being.. I had to tap into the wire for my 3rd brake light to get that extra dedicated "brake only" bulb to work on my truck. You CAN tap into at the 3rd brake light, but that's a pain in the *** honestly. I tapped into mine under the driver's seat and drilled a hole and put a grommet in there to run the wire out. Years later I found out there are already rubber grommets on the floor in several spots, if pull back your flooring you can find them under the seat also.
As for the dome light, easiest way is to run a wire from the battery with an in-line fuse.. you can tap into in the cab, but you're gonna have to get it out of the cab one way or another.
Also, how I did it on my F250, I found some 3 wire plugs, as my camper shell had a 3 wire plug on it, and i added one to the truck bed, so I can easily unplug it and remove it if need be. I think for that.. and you MIGHT be able to do it on yours.. is tap into your trailer light wiring harness (might not work with the 4 wire plug, but will with a 7 wire plug). Sometimes you have a brake wire (blue I think?) you can tap into.. and one is a power accessory wire you can tap into for the dome.. but it's not hot all the time, just key-on hot.
Point being.. I had to tap into the wire for my 3rd brake light to get that extra dedicated "brake only" bulb to work on my truck. You CAN tap into at the 3rd brake light, but that's a pain in the *** honestly. I tapped into mine under the driver's seat and drilled a hole and put a grommet in there to run the wire out. Years later I found out there are already rubber grommets on the floor in several spots, if pull back your flooring you can find them under the seat also.
As for the dome light, easiest way is to run a wire from the battery with an in-line fuse.. you can tap into in the cab, but you're gonna have to get it out of the cab one way or another.
Also, how I did it on my F250, I found some 3 wire plugs, as my camper shell had a 3 wire plug on it, and i added one to the truck bed, so I can easily unplug it and remove it if need be. I think for that.. and you MIGHT be able to do it on yours.. is tap into your trailer light wiring harness (might not work with the 4 wire plug, but will with a 7 wire plug). Sometimes you have a brake wire (blue I think?) you can tap into.. and one is a power accessory wire you can tap into for the dome.. but it's not hot all the time, just key-on hot.
RonD, I'm hoping you see this question. I was looking for the violet wire, and I only have two grey wires, a green, a green with red stripe, and a red with green stripe coming from my brake pedal. I believe the solid green is power, as it is a much bigger wire, 14 gauge maybe, and the rest are smaller, 18 or 20 gauge. So, my question is did ford just use whatever was the right size laying around, or did they have a different color scheme for later years (I'm a 2004 Edge). Thanks, and sorry to bring back an old thread.
Yes, Ford changes wire colors
Brake pedal switch has TWO switches inside, one for brake lights and one used as a "sensor"
My 2004 diagram shows a Light Green wire from brake pedal switch that splits to two wires, one to 3rd Brake light and one to Multi-function switch, both are also light green
Green with red stripe comes from the brake light fuse #19 20amp, this is always "live"
For "sensor"
I don't see grey wires but do see a brown wire from fuse #32 5amp and a red/light green stripe out to various units, like 4x4, cruise, shift interlock
Brake pedal switch has TWO switches inside, one for brake lights and one used as a "sensor"
My 2004 diagram shows a Light Green wire from brake pedal switch that splits to two wires, one to 3rd Brake light and one to Multi-function switch, both are also light green
Green with red stripe comes from the brake light fuse #19 20amp, this is always "live"
For "sensor"
I don't see grey wires but do see a brown wire from fuse #32 5amp and a red/light green stripe out to various units, like 4x4, cruise, shift interlock
Last edited by RonD; Oct 27, 2018 at 09:47 PM.
Yes, Ford changes wire colors
Brake pedal switch has TWO switches inside, one for brake lights and one used as a "sensor"
My 2004 diagram shows a Light Green wire from brake pedal switch that splits to two wires, one to 3rd Brake light and one to Multi-function switch, both are also light green
Green with red stripe comes from the brake light fuse #19 20amp, this is always "live"
For "sensor"
I don't see grey wires but do see a brown wire from fuse #32 5amp and a red/light green stripe out to various units, like 4x4, cruise, shift interlock
Brake pedal switch has TWO switches inside, one for brake lights and one used as a "sensor"
My 2004 diagram shows a Light Green wire from brake pedal switch that splits to two wires, one to 3rd Brake light and one to Multi-function switch, both are also light green
Green with red stripe comes from the brake light fuse #19 20amp, this is always "live"
For "sensor"
I don't see grey wires but do see a brown wire from fuse #32 5amp and a red/light green stripe out to various units, like 4x4, cruise, shift interlock
Once again, your knowledge astounds me. So, tap into the green with red stripe and run that back to my shell's power wire is what it sounds like will be the route here. ill include the 5 amp fuse like you recommended further up the thread
Yes, green/red stripe wire would work for full time power for canopy dome light, I don't think brake light power is on battery saver system, so if dome light is left on then battery would go dead.
The light green wire should also be run to canopy for its 3rd brake light
Yes any added wire should have an inline fuse added, and this fuse should be as close as practical to the power source, brake light fuse
Putting the fuse at the other end of the wire doesn't help much, lol, since short is more likely to occur on the added wire run not at the device it powers, but fuse at the source would blow in either case, fuse at device end wouldn't
This would apply to dome light wire and 3rd brake light wire if used, but would need inline fuses
The light green wire should also be run to canopy for its 3rd brake light
Yes any added wire should have an inline fuse added, and this fuse should be as close as practical to the power source, brake light fuse
Putting the fuse at the other end of the wire doesn't help much, lol, since short is more likely to occur on the added wire run not at the device it powers, but fuse at the source would blow in either case, fuse at device end wouldn't
This would apply to dome light wire and 3rd brake light wire if used, but would need inline fuses
Last edited by RonD; Oct 28, 2018 at 01:51 PM.
Ron, you are the man. Spliced in to the light green wire, now I have a working 3rd brake light on my shell. It didn't come with a dome light, so I'm going to hold off on splicing into the green/red wire until I get there. Thanks for the help on the wirinf, i appreciate you taking the time to dig into the books on my behalf.
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