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

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Doubeleive

Wes
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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.
 
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George B

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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

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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

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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

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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...
rps20200407_173952_125.jpg

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.
 
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MP40Gunner

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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

Wes
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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

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@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.
 
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