GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Page 1 of 2 12 LastLast
Results 1 to 10 of 12

Hybrid View

  1. #1

    Default GMLAN data bus system

    Been doing some research on the GMLAN data bus system, but can't seem to find a direct answer. I purchased an aftermarket stereo and $5 wiring harness to install in my 06 Silverado. While I was reading about the wiring I came across the device known as the GMLAN data bus system. What exactly does this GMLAN do, where is it located and what functions will I lose by removing my factory radio? My truck doesn't have OnStar or the Bose audio system.

  2. #2

    Default

    I'm not 100% on what all it does do but I'm pretty sure it controls your door chimes. That system may also control your steering wheel controls if you have them.

    I literally just got my aftermarket stereo in the mail yesterday from Crutchfield, and mine came with a Metra GMOS-04 interface which keeps the door chimes as well as keeps the factory amp in my Bose system working.

    As to where it goes, mine plugs into the truck's harness and then the other side of the interface is wired into the plug that came with and connects to the stereo. So I would assume that the GMLAN is probably the truck's onboard computer system and then the factory radio contains the interface which outputs the door chimes and onstar sound.

    I don't really know much about this though, so don't take this to the bank. All I can say for sure is that you need some aftermarket interface if you want to keep the chimes.
    WAR EAGLE!!!

  3. #3

    Default

    Most if not all the extras (Onstar, Factory Bluetooth, warning chimes, and I am sure I am missing something) all run through the radio. The harness keeps those things working. So in your case the only thing you need is for the chimes. PAC audio has one for like $50.





    2011 GMC Sierra SLE - 5.3 - 4X4 - Z71 - King Shock Level Kit - Body Color GMC grill emblem - 2 Tone Engine Cover, Rad Cover and Battery Box - Volant CAI - Tru Cool 40K tranny cooler - Sylvania ZXE bulbs Hi/Low -TriFold Hard Tonneau Cover- CoverCraft Seat Covers - Diablo inTune - GoRecon LED under rail lights - GoRecon LED White Lightning Tailgate Light Bar - Windows tinted to 45%- Kenwood DNX6990 - JL Audio C5-650 &650X- JL Audio Amp- Interco Truxus M/T 33x12.50x18

  4. #4

    Default

    So in reality I should be able to use the $5 harness to operate my after-market stereo and the only function I will lose is door, key and light chimes? I will admit that sometimes those chimes can get annoying, but I understand their purpose.

  5. #5

    Default

    Quote Originally Posted by egcz71 View Post
    So in reality I should be able to use the $5 harness to operate my after-market stereo and the only function I will lose is door, key and light chimes? I will admit that sometimes those chimes can get annoying, but I understand their purpose.
    I'd say so. Silverado radio's are so easy to remove and re-install I'd just try it with your harness and see if you notice anything else wrong other than the chimes. If there is a problem or you want the chimes back, it should only take a few minutes to hook up an aftermarket interface. And I think the price range on a basic interface is around $40 -50. I know there are lots on Amazon. I think Walmart even carries one in their audio electronics brand.
    WAR EAGLE!!!

  6. #6

    Default

    Quote Originally Posted by egcz71 View Post
    Been doing some research on the GMLAN data bus system, but can't seem to find a direct answer.
    Just a quick overview, the GMLAN is a Local Area Network that connects all of the control modules within the vehicle. The radio is only one of those modules, others include (as someone suggested) the Onstar module, the HVAC, the ABS, the Traction control, the Powertrain Control Module, the Transfer Case Control Module, the Door control modules, etc, etc, etc.

    The technician uses the ODB2 port and a TECH 2 analyzer to diagnose the systems.
    Ray

    '09 Avalanche LTZ - Black
    '05 Envoy XL (sold)

  7. #7

    Default

    What I'm thinking about doing now is just using the $5 harness I have and then running a 12v ignition wire for the aftermarket CD player. I like not having the door chimes hooked up, but I would like to retain the feature that leaves the radio turned on after the key has been turned off. What circuit can I run the cd players 12v ignition wire to to keep that function?

  8. #8

    Default

    Quote Originally Posted by RayVoy View Post
    Just a quick overview, the GMLAN is a Local Area Network that connects all of the control modules within the vehicle. The radio is only one of those modules, others include (as someone suggested) the Onstar module, the HVAC, the ABS, the Traction control, the Powertrain Control Module, the Transfer Case Control Module, the Door control modules, etc, etc, etc.

    The technician uses the ODB2 port and a TECH 2 analyzer to diagnose the systems.
    Only thing I know about the databus is that when I installed a remote starter I had to buy a special cable to connect to it,

    1995 Silverado 4x4
    6" BDS Suspension Lift-3" Body Lift-Add A Leaf in rear -Trailmaster SSV Shocks-Duel Steering Stabilizer Kit -AirAid Cold air intake-
    4.56 Gears with Detroit Auburn Locker-Pro-Comp Traction Bars with duel shocks-Aluminum Skid Plate Kit-38.5" x 16.5" Mickey Thompson Baja Claws-Constant Dropping fuel gauge

    2005 Yukon XL Jet Power Programmer, Bilstein Shocks, Bilstein rear springs, Helwig Anti-sway bars, EGR Window Visors, EGR Hood Shield, Denali Headlights, Headlight harness upgrade, GE NightHawk Bulbs, White Night Rear lighting system, Russell Braided SS brake lines, PowerStop Brake pads, PowerStop cross drilled and Slotted Rotors, http://www.gmtruckclub.com/forum/sho...5-GMC-Yukon-XL
    2002 Silverado ext cab 2wd (Sold)
    2003 Yukon XL (Totaled)

  9. #9

    Default

    Quote Originally Posted by Pikey View Post
    Only thing I know about the databus is that when I installed a remote starter I had to buy a special cable to connect to it,
    It's a Local Area Network; actually, may be considered 2 LANs, a high speed network and a low speed network. The low speed is used for the human to vehicle interface (push a door lock button, the door modules lock the doors). The high speed is for the communications between various vehicle control modules and their sub-modules (powertrain, body control, audio, brakes, etc). Most of the modules have 2 states, "awake" and "asleep". An idle state will induce some modules into the "asleep" mode, while others are commanded into that mode. The modules have battery power when the ignition is off, turning on the ignition commands the modules into the "awake" state. Things like the Retain Power feature, are software controlled; these modules stay "awake" for a defined time after the ignition is switched off. At the end of the defined period, the BCM (I think it's the BCM) commands these modules to sleep.
    Ray

    '09 Avalanche LTZ - Black
    '05 Envoy XL (sold)

  10. #10

    Default

    Wow, Thanks @RayVoy ! Excellent explanation.

    1995 Silverado 4x4
    6" BDS Suspension Lift-3" Body Lift-Add A Leaf in rear -Trailmaster SSV Shocks-Duel Steering Stabilizer Kit -AirAid Cold air intake-
    4.56 Gears with Detroit Auburn Locker-Pro-Comp Traction Bars with duel shocks-Aluminum Skid Plate Kit-38.5" x 16.5" Mickey Thompson Baja Claws-Constant Dropping fuel gauge

    2005 Yukon XL Jet Power Programmer, Bilstein Shocks, Bilstein rear springs, Helwig Anti-sway bars, EGR Window Visors, EGR Hood Shield, Denali Headlights, Headlight harness upgrade, GE NightHawk Bulbs, White Night Rear lighting system, Russell Braided SS brake lines, PowerStop Brake pads, PowerStop cross drilled and Slotted Rotors, http://www.gmtruckclub.com/forum/sho...5-GMC-Yukon-XL
    2002 Silverado ext cab 2wd (Sold)
    2003 Yukon XL (Totaled)

Page 1 of 2 12 LastLast

Similar Threads

  1. BlackBear Data log
    By sierra11 in forum Performance & Fuel
    Replies: 10
    Last Post: 11-10-2012, 10:17 AM
  2. 4.3l engine data and help on diagnosis.
    By randyr8845 in forum GM Powertrain
    Replies: 16
    Last Post: 07-01-2012, 12:44 PM
  3. Chevrolet : Silverado 1500 V8 Truck, Mp3 XM Satelite Radio Data System
    By Steve in forum Chevy Trucks For Sale eBay
    Replies: 0
    Last Post: 04-08-2011, 06:10 PM
  4. MAF reading 0 g/s on data list???
    By 10mmguy83 in forum General Chevy & GM Tech Questions
    Replies: 4
    Last Post: 02-16-2011, 11:10 AM
  5. Chevy Truck Dimensional Data
    By psychotrshman in forum Chevy Truck Tech Forum
    Replies: 9
    Last Post: 11-12-2010, 12:11 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •