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Four Brake lights and turn signals

I have tried to do this mod to my 03 Z71 (using 3 diodes per side). The right side works fine. When I did the left side everything works well by itself, but if I use left turn and brake, the diode to the lower light (turn) gets REAL HOT and there is no flash turn (they freeze). I have changed diodes out and checked to make sure they are the right way. Any ideas before I switch to the relay method?
 
If the turn signal doesn't flash it is because the diode coming from the brake light is either in backwards or it is bad. Since you changed them and it still doesn't work, it would seem like another problem, but that is not the case. Changing to the relay system isn't a bad idea anyway, but it shouldn't be necessary.
 
TRz66 said:
Hey - Sperry or anyone else who knows what I should do,

I did the traditional 4-way brake mod with the diodes to trailer harness and I'm having trouble with my trailer lights when hooked up. There is a serious delay, if my turn signals even blink, when I brake and use my turn signals. You had mentioned LED lights w/o load resistors; where you talking about the trailer's lights or the AVs brake/turn lights? If you were talking about the trailer, would it go back to normal if my trailer had the LEDs brake/turn lights?,

Any help would be greatly appreciated, (y)
Troy

Yes, relays are only needed on large trailer brake/turn loads.

Mine worked the same with or without a trailer connected. The diodes I added were for the upper to operate with some more logic: Both will show on turn or brake. The brake overrides turn on the upper and the turn overrides brake on the lower.

If you just brake, both will light (each side) OR if you just have the turn sig on, both will flash.

You need the (3 to 6 Amp) diodes if you want this (upper) functionality added to the lower turn/brake mod.

However, fot those whom hadn't done it yet, and If you want to just add brake light function to the lower lamp's turn function, you route the trailer turn & brake signal wiring to the lower lamps, and remove their original wire connection. No diodes needed for this.

The fuses for the trailer turn & brake (in the left dash fuse panel - 03+) are just 10Amp for each side. A brake light filament draws around three amps each and with a simple trailer, you are running up to three filaments through those fuses, in turn signal mode each side, with how I did the (complete) mod.

So far, I hadn't needed the LED mod.

In brake "mode" the upper filament is sourced in combination with the original wiring, isolated with the diodes..

If you used 1 Amp diodes such as a 1N4001 through 1N4007, per se', you could have overheated it with the load and shorted it. Now the circuits have lost their isolation from one-another and weird things can occur.

If a "trailer brake and turn" fuse is removed or blown, with this mod, the turn flasher will flash rapidly.

I hope I didn't leave you too confused.. Perhaps more info as we proceed...
 
I got the problem solved. The right side was easy. On the left side I thought I would get all my connections made and do all the soldering at once. Well- tonight I started over, all is hooked up right and diodes going the right way. Let's check the feeds. Guess what?
You can't interchange the turn and brake Lt blue wire feeds. I guess when I cut the feeds for the turn and brake to put in the diodes, I exchanged the wires and had them backwards. On the right side they are different colors. Oh well that is why I am a Mechanical Engineer and not Electrical.
Darn pesky electrons!
 
JHC

  We need to get more AV owners to complete this mod!

  It is difficult to enjoy this mod when you are driving and can not see them in the back  :C:

  If only all AVs had this, then we can be annoyed by all the brake lights on, especially when you have the LOF and trailer hitch brake light!  >:D
 
I agree. It is one of the best mods that I have done that I can't really enjoy.

However, I do get satisfaction just knowing that the driver behind me will have a better chance of seeing my brake lights. I sometimes wonder if other Av owners notice that my lights are different than their's.

I wonder how many have actually completed this mod.
 
has anyone installed led's w/ this mod to see how it reacts...Meaning maybe, just maybe, you wouldn't need the resistors to make the turns flash normal and for the cruise control to work.
I just installed led's this week and have those problems...and want to do this mod...and wondering if this mod adds enough load for these things to work properly.
Thanks,
Damon
 
Tdybr27 said:
JHC, you'll have to do mine at one of our GTG's.? ? BTW, you goin to Hooters on the 28th?

Chris,

I can do the mod for you anytime.
I'm planning on being there on the 28th.

Jim
 
Is this another mod I'm gonna have to read all the way through and figure out how to do it, or is there a quick, easy, and painless way to do it?? :D

No one ever posted any pictures of the original modification.........what happened?
 
JHC said:
The diagram is in post #10 on page 1. If you have any questions just ask.

Thanks JHC......I figure this mod is a must now that I've got my tail lights smoked I need all the brake lighting I can get back there.  I'll take a look at it and get the parts hopefully before the weekend.  Hopefully once I take a look at the wiring I'll have a better feel for what I'm doing.

First question is how are you securing the diode to the wire, I don't think electrical tape would be good enough for this connection? 

Thanks again,

bb
 
That's definately the most reliable. Just not so reversable if there was a warranty issue.

Scotch locks only leave an insulation cut, if you use the correct size. The problem with them is the weather exposure and corrosion/contaminates. Tape gets gooey, slit wrap hardens... But the heat shrink over the soldered connection is simply the most reliable and safe.

One should tie the wiring so there is no strain on the diode leads.
 
BigBlackAv said:
has anyone installed led's w/ this mod to see how it reacts...Meaning maybe, just maybe, you wouldn't need the resistors to make the turns flash normal and for the cruise control to work.
I just installed led's this week and have those problems...and want to do this mod...and wondering if this mod adds enough load for these things to work properly.
Thanks,
Damon

You've probably answered this question yourself by now, but if you haven't......yes you still will need the load resistors for proper cruise and blinker operation.  Now my question to you is where and how did you mount the resistors?

Thanks,

bb
 
at first I couldn't find the little junction box w/ all the connectors...I wanted to put them all by it and I had seen pics of it, but assumed it was on  the drivers side... well I couldn't find it and just put it on the turn signal wire right where it leaves the frame and comes up into  the body panel to go to the tail light and there was a hole in the frame that I tucked the resistor into and again for the brake lights....on the passneger side, I see there is the junction box I had seen pics of and I located it there and screwed the resistor to the back side of the body panel....one day I will relocate them all over there, but when I did it, it was the last day of STI and did not want to drive such a long trip w/out cruise control.
So my tips are ... locate all three (one for stop and one for each turn) on the back of the right rear quarter panel near the junction box.
and don't use the hazards as a way to hunt down the turn signal...it don't work, I don't know why, but it just don't.
 
BigBlackAv said:
has anyone installed led's w/ this mod to see how it reacts...Meaning maybe, just maybe, you wouldn't need the resistors to make the turns flash normal and for the cruise control to work.
I just installed led's this week and have those problems...and want to do this mod...and wondering if this mod adds enough load for these things to work properly.
Thanks,
Damon
I am also planning to do the Line of Fire and Sail Panel LED's and hoping that all these LED loads would add up to not needing the resistors.
 
BigBlackAv said:
at first I couldn't find the little junction box w/ all the connectors...I wanted to put them all by it and I had seen pics of it, but assumed it was on? the drivers side... well I couldn't find it and just put it on the turn signal wire right where it leaves the frame and comes up into? the body panel to go to the tail light and there was a hole in the frame that I tucked the resistor into and again for the brake lights....on the passneger side, I see there is the junction box I had seen pics of and I located it there and screwed the resistor to the back side of the body panel....one day I will relocate them all over there, but when I did it, it was the last day of STI and did not want to drive such a long trip w/out cruise control.
So my tips are ... locate all three (one for stop and one for each turn) on the back of the right rear quarter panel near the junction box.
and don't use the hazards as a way to hunt down the turn signal...it don't work, I don't know why, but it just don't.


Thanks BigBlackAv.........I was hoping to avoid drilling or screwing into the frame of the truck.  I wasn't sure how hot the resistors got, and I wanted to try some double sided Super strenght 3M tape.  But it seems like screwing into  the frame might be unavoidable.
 
they do get hot...420greg had them 3m taped to the side of the taillight bucket and his fell behind the tailliight and it melted the little scotchloc connectors where it touched...w/ a sharp point pan head screw it is easy to screw them in place...I just wish I did the passenger side 1st so I could have them all together on one side. and remember you only need to do one for the brakes...you don't need to do both sides to get you cruise working.
 
blackbeauty said:
You've probably answered this question yourself by now, but if you haven't......yes you still will need the load resistors for proper cruise and blinker operation. ? Now my question to you is where and how did you mount the resistors?

Thanks,

bb

I stand corrected......you do not need to add the resistors when you perform this mod.? I suppose when I checked my blinkers last weekend I hadn't done both sides.? Well today was my first day driving the AV since I did the mod and the flasher and cruise control are working perfectly fine.? Sorry for the mistake.

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Do you have sailpanel led's?
and I thought that might be the case...when I had a trailer connected the quick flash and cruise problem went away...damn....I'll get those on and pull the resistors out....
That looks much brighter..can you take another w/ just the running lights on?
 
man, I need to get this mod done!...that looks great!
 
BigBlackAv said:
Do you have sailpanel led's?
and I thought that might be the case...when I had a trailer connected the quick flash and cruise problem went away...damn....I'll get those on and pull the resistors out....
That looks much brighter..can you take another w/ just the running lights on?

I think I'm just going to keep my mouth shut.....because I just went out to take a pic with just the running lights and now the flasher is going crazy fast.? And nooooo I haven't been drinking? ;)........I'm now perplexed as to why when I went out earlier the flasher and cruise were working perfectly fine, now at dusk the flasher is once again blinking very quickly. ???

But here is a pic of just the running lights.

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Being that it's not as bright outside as it was earlier, it's kind a hard to tell the difference in the LED brightness.
 
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