Jump to content

T1 Dome Light Tap Wires

Smoothbassman

By Smoothbassman
in Modifications, Wheels & Tires

 Share

Recommended Posts

Smoothbassman Enthusiast

Smoothbassman

Posted
Posted

Just got thru installing my floor lighting. Looks great but now I need to tap into the dome light circuit to get them to turn on when I open the doors.

 

Does anyone have a clue on the 2019-2020 Silverado. I need to get this done. This was so simple on the 2014s. 4d2a32151a2431b57f5e4566f8f66dc5.jpg

 

Sent from my SM-N960U using Tapatalk

 

 

  • Like 1
  • Replies 35
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

Smoothbassman
Smoothbassman

This is easy. Get you a strip of LEDs and tap into the dome circuit. When you open the door lights on. If you pull too much current then the BCM will trip out so go light in the LEDs and you shoul

DNTBL8
DNTBL8

Smoothbassman, thanks so much for the help. i ended up doing 3 LEDs that were bolt style (not strip) directly off the BCM without a relay, no buzzing, no BCM freakout. Here's a post I made that shows

Smoothbassman
Smoothbassman

Just got thru installing my floor lighting. Looks great but now I need to tap into the dome light circuit to get them to turn on when I open the doors.   Does anyone have a clue on the 2019-2020 Silv

Posted Images

Echo5625 Enthusiast

Echo5625

Posted
Posted

I’m in the same boat, wanting to do this for footwell . I believe there is a grey wire in the bcm not 100%. Another option is the dome light wire in the driver A pillar. 

Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted

Ok after testing most of the wires in the BCM I finally found the one that I need to make this whole thing come together.

Pin 10 on the forward most BCM connector gives me the positive output for the dome lighting.

After testing the Opt 7 lights I found that I can't turn the courtesy lights on without the main light controller on so I'm going to have to rethink the electrical. I'm currently running it on accessory power and that's not going to work. I need the power to come on when I open the door, and be active when I'm rolling down the road. Going to have to add some relay logic to get this thing working the way I want.

More to come this week. 714cb6264c7b2b90406871def400f4cd.jpg

Sent from my SM-N960U using Tapatalk

Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted
I’m in the same boat, wanting to do this for footwell . I believe there is a grey wire in the bcm not 100%. Another option is the dome light wire in the driver A pillar. 
Crazy thing is I checked the A pillar and all of the wiring has been rerouted in the T series trucks. Nothing there but an airbag. They might have taken it thru the B pillar. Don't want to have to tear that all apart.

Sent from my SM-N960U using Tapatalk

Echo5625 Enthusiast

Echo5625

Posted
Posted
4 hours ago, Smoothbassman said:

Ok after testing most of the wires in the BCM I finally found the one that I need to make this whole thing come together.

Pin 10 on the forward most BCM connector gives me the positive output for the dome lighting.

After testing the Opt 7 lights I found that I can't turn the courtesy lights on without the main light controller on so I'm going to have to rethink the electrical. I'm currently running it on accessory power and that's not going to work. I need the power to come on when I open the door, and be active when I'm rolling down the road. Going to have to add some relay logic to get this thing working the way I want.

More to come this week. 714cb6264c7b2b90406871def400f4cd.jpg

Sent from my SM-N960U using Tapatalk
 

What about the ambient light circuit, I believe that’s on with door/remote and stays on while in motion? Also is this harness under the drivers side ?

Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted
What about the ambient light circuit, I believe that’s on with door/remote and stays on while in motion? Also is this harness under the drivers side ?

Yes. It's the harness under the drivers side dash.

 

I really don't like tapping into wires in the BCM, but there's no way around it on this truck. Even found that the new dome lights are solid state on a circuit board when removing the center overhead panel. No way to tap in without knowing how to do surface mount soldering.

 

I'll have to test that ambient light circuit.

 

What's crazy is all of the wiring for everything is already there for features my truck doesn't have like the automatic dimming mirror and the homelink connection. It's even currently powered up.

 

Now only if I can find a wrecked T1 in a salvage yard. I will be racking up on some parts. 446e6b41f614082faf3e6921b5193d7d.jpg

 

Sent from my SM-N960U using Tapatalk

 

 

 

Echo5625 Enthusiast

Echo5625

Posted
Posted
15 hours ago, Smoothbassman said:

Yes. It's the harness under the drivers side dash.

 

I really don't like tapping into wires in the BCM, but there's no way around it on this truck. Even found that the new dome lights are solid state on a circuit board when removing the center overhead panel. No way to tap in without knowing how to do surface mount soldering.

 

I'll have to test that ambient light circuit.

 

What's crazy is all of the wiring for everything is already there for features my truck doesn't have like the automatic dimming mirror and the homelink connection. It's even currently powered up.

 

Now only if I can find a wrecked T1 in a salvage yard. I will be racking up on some parts. 446e6b41f614082faf3e6921b5193d7d.jpg

 

Sent from my SM-N960U using Tapatalk

 

 

 

thanks, all good information here, extremely helpful with future options of adding upgrades. im going to look into the bcm connection this evening see what i can gather, i really want to find that dome wire lol

Coolade Enthusiast

Coolade

Posted
Posted

The dome wire is a gray wire in the passenger A pillar, but be careful, there are two gray wires in the wire loom.  I installed a set of led light strips under the doors that have running lights in them and also a set of white lights that will illuminate each time a door opens.  

  • Like 1
Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted

Ok,

In order to get the OPT-7 Lights to work properly the system has to be powered on when the door tigger switch is activated. I think this is a poor design, and I hope they fix that in future versions. That aside, this is a 10 dollar fix for this situation, and allows you to run the courtesy lights, as well as get the lights turned off automaticaly when you leave the vehicle using a couple of relays.

I finally got everything bench tested and really for final installation in the truck. Heres the explanation on it

83a15ab4cf5827c722871773e5148432.jpg

Legend

Pin 1 - Constant Power
Pin 2 - Switched Power
Pin 3 - Door Trigger
Pin 4 - Relay Power Bridge
Pin 5 - Opt 7 Power Output
Pin 6- Ground
Door- Door Switch Power Relay
Running - Accessory Power Relay

So at a high level when the door relay is idle it passes current to the accessory relay thru the normally closed pin to the accessory relay which closes that switch. If there is no accessory power on the lights don't come on.

Once the door opens it closes the door relay and opens the running relay and the lights turn white.

Door closes and I turn on the truck, the running relay is now powered passing power direct to the lights and they turn back to the preselected color that you set.

Bench tested this setup and it works great. Going to install on the truck this week.

Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted

Installed it today.

Works perfectly!!

I have to add a filter and capacitor to stop the relay from buzzing due to the dimming feature of the lights dropping the voltage below the needed 12V to lock up the relay constant power relay.

Video link below.



Sent from my SM-N960U1 using Tapatalk

  • Like 1
Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted

Added the filter and now it works perfectly. Only sound you hear is the relay clicking on solidly.


Sent from my SM-N960U1 using Tapatalk

Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted
Added the filter and now it works perfectly. Only sound you hear is the relay clicking on solidly.


Sent from my SM-N960U1 using Tapatalk




Sent from my SM-N960U1 using Tapatalk

  • 3 months later...
DNTBL8 Enthusiast

DNTBL8

Posted
Posted

This is incredibly awesome post. Very cool that you figured it out ? for your needs going down the road. However, I am now a bit confused on how to accomplish my simple mission when I began searching this thread...

 I just want a simple set of foot-well lights ( two simple LED strips) to come on when the doors open and go off when the doors shut.  Which wire would I tap into for that, I plan on using a T-tap near the harness. Would that be ONLY pin 10 for my needs?

 

Also if I may rant as a newbie to the forum (GM truck guy my whole life)- It is totally bogus that the lighting in the T1 is not only extremely limited, but focused to one spot-. with jet black interior I can't find anything at night in the floorboards!

TXguy Enthusiast

TXguy

Posted
Posted
On 10/8/2019 at 5:06 AM, Smoothbassman said:

 


Sent from my SM-N960U1 using Tapatalk
 

 

Have you drawn a wiring diagram for this?  I would love to install in my truck 

Smoothbassman Enthusiast

Smoothbassman

Posted
  • Author
Posted
This is incredibly awesome post. Very cool that you figured it out [emoji106] for your needs going down the road. However, I am now a bit confused on how to accomplish my simple mission when I began searching this thread...
 I just want a simple set of foot-well lights ( two simple LED strips) to come on when the doors open and go off when the doors shut.  Which wire would I tap into for that, I plan on using a T-tap near the harness. Would that be ONLY pin 10 for my needs?
 
Also if I may rant as a newbie to the forum (GM truck guy my whole life)- It is totally bogus that the lighting in the T1 is not only extremely limited, but focused to one spot-. with jet black interior I can't find anything at night in the floorboards!
This is easy.

Get you a strip of LEDs and tap into the dome circuit. When you open the door lights on.

If you pull too much current then the BCM will trip out so go light in the LEDs and you should be OK.

Sent from my SM-N960U1 using Tapatalk

  • Like 2

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • KARNUT
      Gas Prices

      By KARNUT · Posted

      3.19 @ Kroger’s in Montgomery Tx
    • Flynlow
      2027 Chevrolet Silverado: Official Discussion

      By Flynlow · Posted

      We have now!  2027 GMC Sierra  Early look, but I'm a GMC guy and so far I think I like the looks of the Chevy better.
    • newdude
      Lower trims ( WT, Custom, Silverado ( aka LT )

      By newdude · Posted

      HD at the moment, are kinda their own deal.  How LTZ sells on those vs on 1500, there is a difference.   They are merging most of the mid trims on 1500.  LT, RST and LTZ are replaced by one trim, Silverado.  LT and RST are a BIG portion of sales.    Bad naming choice aside, the new Silverado trim will offer the spread of options that those three trims offered.  So expect to see things like the tech package for example, and memory seats.  And LT Trail Boss will now just be "Trail Boss" (formerly LT Trail Boss) but will offer content spread like the new Silverado trim will.  The press photos showed the Trail Boss (formerly LT Trail Boss) has access to Super Cruise now, which on the current truck was High Country only.       Here is the Trail Boss interior.  Memory seats and Super Cruise are present.  All things the LT Trail Boss it replaces, and the RST it was based on didn't get on the current gen.  You had to go to LTZ or ZR2 for memory seats, and High Country for Super Cruise.      
    • dennismc
      2021 vs 2026 handling (1500 X31 Sierra)

      By dennismc · Posted

      I installed a Hellwig rear sway bar on my 21 Sierra SLT, it made a huge difference on how the truck handles, no body roll, the trucks much more planted now. Not sure of the suspension differences between the 21 and 26,  if its body roll your having a sway bar will solve it. 
    • Old Bay
      frustrating P0446 code

      By Old Bay · Posted

      So a follow up and my fix. I found in online searches the live data to look at on a scan tool to verify the fuel tank pressure sensor was working.  It showed an spec number towards the lower end of the rang, but in spec.  Then while it was running opened the gas cap and the pressure should change.  It didn't change even a tiny bit.  The data for the purge valve said it was open...never changed. So then I measured the voltages on the plug for the fuel pressure sensor and they matched what it should be.  So local car quest parts had the sensor in stock...it was a bit of a pain to remove and an even bigger one to get it to actually go back in.  It helped to unbolt the driveshaft and bungie cord away from the gas tank to give a bit more room to work. So fuel tank pressure sensor in I cleared the code, and started it up.  I went to the scan tool's live data and... Eureka! The pressure number was different and fluctuated a bit.  So took it on a short drive and pressure number varied saw the purge valve go from closed to open and back to closed.  Drove it to and from work for roughly a week plugged in the scan tool no codes.  I took it in to get tested and passed.  In my state's infinite wisdom (oops meant greed), since I pushed the test with the maximum extensions I have to take it back in by Feb '27 to 'get it back up to date', then my next test won't be until Feb '29. 

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...