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Four Brake lights and turn signals

JHC

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I connected all 4 lights to work with the brakes and the turn signals. When the turn signal is on, only the top light functions as a brake light (as normal) and when the brakes are applied, only the bottom light functions as a trun signal (as normal).

But if the brakes are applied and the turn signal is not on, I have 4 brake lights and if the brakes are not applied, I have 2 lights for the turn signal on either side.

4 brake lights plus the 3rd (or is that the 5th) brake light plus the LOF will certainly get your attention.
 

JHC

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I don't think pictures will help much, since most of it is covered up, but here's what I did.

You will need 6 diodes. I used Radio Shack #276-1101. They are $.59 for 2.

Locate the wires that go to the brake lights and turn signals. In each socket there are three wires. The black wire on the outside is the ground, the center one is the tail light and the other outside wire is the one you need.

Put one diode in each of the brake light and turn signal wires. The diode goes in with the white band toward the bulb.

The rest of the connections must be made between the bulb and the diode to avoid feedback into the other lights.

Assemble two short wires with a diode in each one to connect the turn signals to the brake lights. Connect them with the white band on the diode toward the brake light. This will give you 2 turn signal lights.

To get the 4 brake lights, attach a wire from the right turn signal (I actually attached to the added pigtail between the brake light and turn signal) to the dark green wire in the trailer harness and attach a wire from the left turn signal to the yellow wire in the trailer harness.

I suspect that most of this could be done under the fuse block, but after I struggled with the 4 headlights on mod under it with my big hands I decided to do my wiring in the tail light cavities.

If you need pictures, I will get them.
 

ShapeShifter

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JHC said:
I don't think pictures will help much, since most of it is covered up, but here's what I did.
Maybe not pictures, but a schematic would help. >:D

-- SS
 

ygmn

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not sure I would pass an state inspection with this mod....
 

ShapeShifter

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ygmn said:
not sure I would pass an state inspection with this mod....
If it's done right, I bet the inspector would never notice. It would look like the way it's supposed to be. (y)

If I'm picturing it right, you'd really need to have two trucks side by side to realize the difference. And if you did, you'd think it was the stock truck that was wrong.

-- SS
 

dunes_av

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JHC said:
I connected all 4 lights to work with the brakes and the turn signals. When the turn signal is on, only the top light functions as a brake light (as normal) and when the brakes are applied, only the bottom light functions as a trun signal (as normal).

But if the brakes are applied and the turn signal is not on, I have 4 brake lights and if the brakes are not applied, I have 2 lights for the turn signal on either side.

4 brake lights plus the 3rd (or is that the 5th) brake light plus the LOF will certainly get your attention.

Ok, umm, what 4 lights are you refering to....
 

JHC

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Grey_Av said:
Ok, umm, what 4 lights are you refering to....

The brake and turn signals at the rear. The top two are brake lights, the bottom 2 are turn signals. (but not on mine anymore) :D
 

JHC

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ShapeShifter said:
If it's done right, I bet the inspector would never notice. It would look like the way it's supposed to be. (y)

If I'm picturing it right, you'd really need to have two trucks side by side to realize the difference. And if you did, you'd think it was the stock truck that was wrong.

-- SS

I think you are right. It is something that no one will notice unless they really know their stuff, and even then, it shouldn't cause a problem.
 

dichris

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JHC

I like it...... However, seen I do tow a trailer once in a blue moon, I would add 2 more diodes... on the wires from the trailering harness... too prevent back feed from the turn signals to the trailering turn signals.....
But like I said, I like it!!!!

Will do a resign of my rear fog lamp circuit to include this...... but I do still need those special relays to get the rear fog lamps working....

Again, Good Job.......

dichris
 

txyank1

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JHC said:
I think you are right. It is something that no one will notice unless they really know their stuff, and even then, it shouldn't cause a problem.

Except for the guy behind you at a stoplight trying to figure what blinded him. :cool:
 

JHC

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dichris said:
JHC

I like it...... However, seen I do tow a trailer once in a blue moon, I would add 2 more diodes... on the wires from the trailering harness... too prevent back feed from the turn signals to the trailering turn signals.....
But like I said, I like it!!!!

Will do a resign of my rear fog lamp circuit to include this...... but I do still need those special relays to get the rear fog lamps working....

Again, Good Job.......

dichris

I dont think you need the diodes going to the trailer harness. The turn signals will get power from both places and the brake lights are overridden. I hav my LOF connected to the harness and it works ok.

Actually, you could just cut the turn signal wires at the tail lights. You don't need them since the connection from the trailer harness will do all of the work. I didn't think about that until I had mine finished.
 

openminds

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JHC said:
I dont think you need the diodes goint to the trailer harness. The turn signals will get power from both places and the brake lights are overridden. I hav my LOF connected to the harness and it works ok.

Actually, you could just cut the turn signal wires at the tail lights. You don't need them since the connection from the trailer harness will do all of the work. I didn't think about that until I had mine finished.

I don't see a need either for the trailer lights. They are on an independent circuit from the front aen't they?

I recall seeing trailer brake left/right and run fuses in the block.
 

dichris

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JHC

I dont think you need the diodes goint to the trailer harness. The turn signals will get power from both places and the brake lights are overridden. I hav my LOF connected to the harness and it works ok.

Actually, you could just cut the turn signal wires at the tail lights. You don't need them since the connection from the trailer harness will do all of the work. I didn't think about that until I had mine finished.


You are correct, but as I am going to be wiring up rear fogs using the Turn signal ( Still not comfortable using the Brake Lights as Fogs, but it would now work with this mod of yours ) I do not want to back feed to the Trailering circuit, which feeds the LOF, which I do not want on with the Rear Fog.. Thus my circuit will require the regular circuit for the turn signal in place, thus cutting that wire is not a option for me.

dichris
 

IBOHUNT

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JHC,

It's hard for me to determine from the picture and description so if you would please clarify a connection for me.

As I see the schematic you have a connection between the non band side of a diode on the pigtail that's connected to the yellow in the trailer harness. Is this correct?

Poor ASCII drawing maybe:

Top portion of 4_brake_lights.jpg


|----- GND
|
Bulb --------- Tail Light
|
|---|<|--Brake Light
|
|---|<|--Left Turn (Lt. Blue ) & Yellow in trl harness
 

JHC

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Correct. The wire comes from the trailer harness, connects to the turnsignal wire, then to a diode connected to the brakelight wire. The diode is connected with the white band on the brake light side.

There is also a diode in the brake light wire to prevent turnsignal feedback to the other side, and a diode in the turnsignal wire to prevent brakelight feedback to the other turn indicators.

Hope this helps,
Jim
 

JHC

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A Joey Bed is just another version of the Bedslide. Basically it's a big slide out drawer in the bed. You can see it at
www.joeybed.com
 

JHC

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That's great. I'm glad to see someone else make this improvement. The only drawback to this mod that I can see is that I never see it.
 
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