What did you do to your NNBS GMT900 Tahoe/Yukon Today?

[kbuskill]

it starts out as 3 wires blinker/marker/ground, then it goes into the bulb connector and 2 more wires exit to the corner marker for a total of 5
if I connect just the blinker portion it works, until the marker lights are turned on
if i connect the marker and blinker it works until the marker lights turn on
kind of weird

View attachment 244066 View attachment 244067 View attachment 244068

I think your problem is the way you have the "resistor" you are using wired.

I used something like these...

And you would hook 1 end to the positive turn signal lead and the other side to ground.

Your "resistor harness" has 3 wires... I can only assume that 1 is ground, 1 is parking +, and 1 is turn signal +... you have the parking + and turn signal + hooked together.

I would disconnect those and only try it with one hooked up at a time.

The way its hooked up in your picture you have 12 v going through the 194 side marker bulb and feeding back into the ground side of the resistor harness which defeats the purpose. Hook the black ground wire from the resistor harness straight to ground.

My guess would be that the red wire is probably the turn signal (resistor) side of that harness, but I'm not sure.

 

[Doubeleive]

I think your problem is the way you have the "resistor" you are using wired.

I used something like these...
View attachment 244082

And you would hook 1 end to the positive turn signal lead and the other side to ground.

Your "resistor harness" has 3 wires... I can only assume that 1 is ground, 1 is parking +, and 1 is turn signal +... you have the parking + and turn signal + hooked together.

I would disconnect those and only try it with one hooked up at a time.

The way its hooked up in your picture you have 12 v going through the 194 side marker bulb and feeding back into the ground side of the resistor harness which defeats the purpose. Hook the black ground wire from the resistor harness straight to ground.

it was originally a plug-n-play harness, it works-when just the blinker is on, it also work with just the 1 red or 1 blue wire, I only had them both connected because I was trying different combinations of wiring to try and get it to work when the marker lights were on. I will try what you are suggesting but I think my "fix" is going to be to just make the one corner light a marker light and have the bigger bulb be just a blinker and run the wires accordingly. It seems that the resistor just isn't strong enough when it is used for both the marker light and the blinker.
***maybe I can connect a relay so it cuts the marker light when the blinker is on? I have a couple micro relays that should work

 

[Doubeleive]

so the weather cleared up, I am trying this again, it def won't work when the marker light is on, I have a mini 8616 relay I just need to figure out the wiring to make it cut the marker light when the blinker is on.

 

[Rocket Man]

so the weather cleared up, I am trying this again, it def won't work when the marker light is on, I have a mini 8616 relay I just need to figure out the wiring to make it cut the marker light when the blinker is on.

I can’t see how the marker light and the turn signal are on the same circuit. Did you try connecting the resistor between a ground ( the body) and the turn signal positive wire where it’s a 3 wire harness, before the other harness? The bcm is looking for a load there. If that doesn’t work and you still have hyper flash, you might have to do the same at the rear turn signal wire.

 

[Doubeleive]

I can’t see how the marker light and the turn signal are on the same circuit. Did you try connecting the resistor between a ground ( the body) and the turn signal positive wire where it’s a 3 wire harness, before the other harness? The bcm is looking for a load there. If that doesn’t work and you still have hyper flash, you might have to do the same at the rear turn signal wire.

yes and it works fine until the marker light is turned on, the rear lights have there own built in resistor and work fine
I am going to try this relay and see if I can make it work so I can still have the large marker light.

 

[Rocket Man]

yes and it works fine until the marker light is turned on, the rear lights have there own built in resistor and work fine
I am going to try this relay and see if I can make it work so I can still have the large marker light.

Did you do both sides -passenger and driver - at the same time? I could see there being a problem if you’re trying to do one side and then you turn on both marker lights.

 

[Doubeleive]

got the relay hooked up to run just the marker light and use the blinker as the trigger and it's not seeing the load on the blinker

 

[Doubeleive]

Did you do both sides -passenger and driver - at the same time? I could see there being a problem if you’re trying to do one side and then you turn on both marker lights.

no I haven't tried both at the same time I only have 1 spare light harness to experiment with if i can get it to see the load on the blinker with the relay it should work, otherwise I will just end up with a small corner marker light which is fine just not what I wanted. the blinker function does not cut the ground it cuts the positive signal just have to figure this out

 

[Doubeleive]

well thanks @Rocket Man you were correct with BOTH the plug-n-play resistors installed everything works fine, ain't that a *****

jumped the gun it's not plug-n-play the light harness will have to be spliced the supplied bulb socket does not fit in the housing, not even close.

 

[Rocket Man]

well thanks @Rocket Man you were correct with BOTH the plug-n-play resistors installed everything works fine, ain't that a *****

One thing I’ve discovered is these systems don’t like things out of balance. Glad it worked!

 

[Doubeleive]

One thing I’ve discovered is these systems don’t like things out of balance. Glad it worked!

ya I thought it was going to be plug-n-play the bulb socket doesnt fit o'well i already have one cut up anyway

 

[Doubeleive]

I feel like a crazy person, the resistors only work with there bulb sock and the bulb socket does not fit the housing, because the oem socket has a common ground or something it wont work so I ordered a different set.

 

[George B]

I feel like a crazy person, the resistors only work with there bulb sock and the bulb socket does not fit the housing, because the oem socket has a common ground it wont work so I guess my nest step is to try and order a non oem socket that will fit, **** I don't even know if that will work.

Do you have a wiring diagram for that system you could share?

 

[Doubeleive]

Do you have a wiring diagram for that system you could share?

sorry I do not, @swathdiver may have the diagram

 

[Doubeleive]

I ordered a different set of resistors that have a socket that will fit with a little dremeling, if that doesn't work then screw it I will just have the bcm programmed, wasted to much time on this.

 

[Rocket Man]

I ordered a different set of resistors that have a socket that will fit with a little dremeling, if that doesn't work then screw it I will just have the bcm programmed, wasted to much time on this.

I have faith that you’ll make it work.

 

[kbuskill]

I ordered a different set of resistors that have a socket that will fit with a little dremeling, if that doesn't work then screw it I will just have the bcm programmed, wasted to much time on this.

I dislike these premade resistor harnesses because you don't know what else is inside the box besides the resistor... like diodes and such.

Your factory harness has...

1. Blue wire = turn signal +
2. Gray = running light +
3. Black = ground -

Your resistor harness is a pass through harness. In theory you should be able to connect the Red wire, on the resistor harness, to your trucks blue wire and the black wire, on the resistor harness, to the black wire on the truck harness... off of the same side of the resistor harness without passing through to the other side of the black box.

Do you have a DVO meter?

Can you test resistor for continuity on your resistor harness to verify which wires are hooked to the resistor internally?

My guess is black on either end of harness should read continuity.

Red to black should read resistance.

Blue to blue should read continuity.

Blue to black should read open.


In theory you should be able to hook it up like this...

I drew a gold resistor between the black and blue wires because the black box should act as that gold resistor when wired in this manner.

The small marker light shouldn't have any effect on the turn signal wire as they aren't connected together from the factory. It might blink with the turn signal if the parking lights power gets interrupted (turned off) while the turn signal light is illuminated.

I know on the older S-10s the marker light would flash in sync with the turn signal when the parking lights were off and it would flash opposite the turn signal when the marker lights were on but this was due to how they had it wired. It would ground itself through the turn signal filament in the dual filament bulb.

I wish I was there to look at it with you... I'm certain we could make it work.

 

[MP40Gunner]

Pulled the side moulding off and cleaned up the residual. Still needs a good compound/ polish to remove the last traces of everything, but that will be a different day. All the side mouldings are in good shape and I'll probably sell them to whoever needs some black ones.

 

[Doubeleive]

I dislike these premade resistor harnesses because you don't know what else is inside the box besides the resistor... like diodes and such.

Your factory harness has...

1. Blue wire = turn signal +
2. Gray = running light +
3. Black = ground -

Your resistor harness is a pass through harness. In theory you should be able to connect the Red wire, on the resistor harness, to your trucks blue wire and the black wire, on the resistor harness, to the black wire on the truck harness... off of the same side of the resistor harness without passing through to the other side of the black box.

Do you have a DVO meter?

Can you test resistor for continuity on your resistor harness to verify which wires are hooked to the resistor internally?

My guess is black on either end of harness should read continuity.

Red to black should read resistance.

Blue to blue should read continuity.

Blue to black should read open.


In theory you should be able to hook it up like this...
View attachment 244098

I drew a gold resistor between the black and blue wires because the black box should act as that gold resistor when wired in this manner.

The small marker light shouldn't have any effect on the turn signal wire as they aren't connected together from the factory. It might blink with the turn signal if the parking lights power gets interrupted (turned off) while the turn signal light is illuminated.

I know on the older S-10s the marker light would flash in sync with the turn signal when the parking lights were off and it would flash opposite the turn signal when the marker lights were on but this was due to how they had it wired. It would ground itself through the turn signal filament in the dual filament bulb.

I wish I was there to look at it with you... I'm certain we could make it work.

@200 ohm's on the meter the
red to black reads 22.1
blue to blue??? one end to the other reads 5.2
blue to black reads 26.1

 

[kbuskill]

@200 ohm's on the meter the
red to black reads 22.1
blue to blue??? one end to the other reads 5.2
blue to black reads 26.1

What about red to black on the same end?

Or blue to black on the same end?

Be sure to check it on both ends... ie... red and black on one end and red and black on the other side of the black box... same for blue and black/both ends.

I'm just trying to rule out diodes or other things inside the box.