• If you currently own, previously owned or want to own an Avalanche, we welcome you to become a member today. Membership is FREE, register now!

2002 2500 Dreaded 'CARGO LIGHT ON' issue

2500AVYFLA

Full Member
Joined
Oct 8, 2014
Messages
44
Hi all,

My 2002 2500, just 2 days ago, started with the 'cargo light on' issue.

A search here is indicating a ground fault somewhere, quite possibly in headliner.

Symptoms are
Cargo Light On is constantly displayed, cargo light is off and switch will not turn it on or off.
NO interior lights, at all. No door lights, no overhead lights, nothing. Although gauge lights, etc, work perfect.
Checked all fuses, all good. Checked fuse holders with voltmeter, all have voltage.
Dropped passenger side headliner to look for chafed wire, all seems good.

Last night, after checking everything, I had forgotten to reinstall 10A fuse for nighttime dash lights/radio, and while that fuse was out, I could press  overhead lights on/off (above rearview  mirror and over console) and while they would not turn on, by clicking any one of them the 'cargo light on' would go on and off. I put 10A fuse back in, and 'cargo light on' stays on, and today by taking out 10A fuse, CANNOT get it to repeat what it was doing last night, ie, on/off of any interior light does not affect cargo light on staying on.

I briefly checked my cargo light wiring but didn't seem faulty.

ONLY mod I have done light related was to install red LED bulbs in all doors, overhead console, and vanity lights under dash, and that was done over 8 months ago and all worked fine.

What am i missing?  Would a possible bad LED bulb 'short' the entire loop? Or is this a dreaded phantom orange wire i am going to have to try and hunt down, or some other area I need to check?

Thanks!
 
Depends on your system.

Does the cargo switch only do your cargo lights and do you have one or two?

My '03 has two.

I can offer suggestions once I know more... Could be chaffing at the pass through.. The wiring comes out from the interior from behind the third brake light. To inspect requires removing the center piece. Which may require some new plastic pieces if you break them off.

To remove the piece... The front edge has tape so carefully pull it up after you remove all 6 screws (4 on top and 2 on bottom if memory serves)
Lift straight up and you won't break the plastic retainers.

If that wire is good then it is likely behind one of the panels. The panels come off easy but you MAY have to remove the inner sail panels (have only one retainer.. So unbolt the bolts you can see and pull up on sail panel and it should pop off.)

The side panels have the 4 hold down bolts and one small screw for the saddle bag latch that hold them into place. But have to pull off the inner sail panel as explained.

I suspect if you have an issue it is likely a wire that was rubbed through in the bed under one of those panels.

Rodney
 
My cargo light switch is push button on dash that only turns my cargo light on/off,  amd my '02 only has one cargo light located on driver side.

I did, about 1.5 years ago change my center brake light to a LED syle, so am familiar with removing panels; also painted all my panels about 2.5 years ago so have removed all of them before.

Thanks
 
And now.... my driver lights will not turn on....  :E: :E: :E:

Nighttime, trued to turn on fog lights, and nothing.....
 
You are the first member with a 02 that only had 1 cargo light, but you may want to pull up the circuit board in the under hood fusebox and see if any rodents have been chewing on your wiring.
 
Disconnect your battery before you do pull it up...  Not hard to do but it is apparently a good bedding place for mice. I have heard softener sheets are good to keep them out of stuff.  As long as not conductive there is quite a bit of room under the fuse panel.

Rodney
 
Geesh Rodney I did not think I had to post the obvious, :laugh:
 
Here we go....


1. I DO in fact have TWO cargo lights, guess keeping my tonneau cover bag there all these years I forgot one was on the pass. side too,  :E:

2. Loose wire under fuse box and.... EVERYTHING WORKS!! ALL HAIL RODNEY!!!  (y) (y) (i even disconnected battery first! Lol  :cool:)

SUCH  a relief..... everytime I even mildly consider getting a new truck, I look at the sticker prices, look at my 2500 Avalanche, and go, "nope. Not gonna do it!" Besides, I bought her on '02, and have put 166k on the odometer, and shooting for another 100k!

THANK YOU ALL!
 
Well the gremlin is back...... :E: :E:

Heres the symtpoms.

I had wiggled tightened tbe wires under fuse box and everything went back to normal and functioning.

Yesterday, cargo light on comes on again.....

I checked fuses and fuse in engine compartment for int. Lights was blown. Replaced, all good. Fuse blew again.... cargo light on again...

So today I take middle brake light panel down and disconnect plugs to cargo lights, cargo light on  light goes off. But, fuse is popping the instant I put one in....

Wires to cargo lights looks fine. When i put voltmeter to fuse connections it shows 12-13 volts, but nothing that would indicte a hge volt spike. I even tried a 20A fuse instead of a 15A and it popped immediately.

So, I have no door lights, no overhead lights, no power to sunroof, no engine bay light and no cargo lights....

Not sure where to look next.... thoughts?
 
you have a dead short somewhere....

If fuse pops instantly you have a postive wire touching ground somewhere....

Need to find it
 
Yeah you have a short somewhere and I can't tell you where it is.

Sorry ygmn posted while i was looking for the diagram.
 

Attachments

  • cargolight.png
    cargolight.png
    65.7 KB · Views: 72
MS03 2500 said:
Geesh Rodney I did not think I had to post the obvious, :laugh:

Well MS03... I can share some of my sisters customer support conversations when she worked for phone support for HP while in school...

Like the one where the lady kept opening up her RUNNING computer and used a standard vacuum to remove the dust and can't figure out why the screen is black now and nothing happens.

She did tell one customer to send their computer back to HP for full refund because they were not ready to own one.

So I never assume people know these things... ;)
 
From mentioned symptoms I would point to multifunction accessory switch.

Note that it controls all of the features you say are not working.

I would inspect splice S213 (Connector where wires are connected together)

Also G203 is the common ground for the switch.

If those are good then you may want to consider replacing the switch with a new one and see if symptoms go away. Junkyards should have them, rockauto may even have it. At a minimum you can likely get the part number off the side of the switch and search on amazon/ebay or google for a cheap replacement.

Note that you may have to trace the wiring behind the switch to find the locations of those connectors.

Going to look up the diagrams myself. I also have the documentation MS03 2500 has up through 2009 for all GM vehicles.
 
looking at the diagrams it appears S203 is a major connection and that the ground is a major ground for just about all of the electronics in your vehicle so you would be having other issues if it were in fact just the ground or this splice connector.

Since it is limited to just the components related to your switch I would strongly suggest trying to swap out the switch and see if your issue goes away.

You can also check and insure all of the mentioned bulbs are properly installed. I have had issues in the past with weird issues due to improperly seated bulbs.

Rodney
 
Lots of great info!

Am I correct in saying the multi function accesory switch is the 2-button switch that turns the cargo lights on and powers my fog lights?? Or is it the round 'dimmer' switch that is part of the headlight switch??


Schematic is fantastic and a great help.

Also, my fog lamp switch has for ages been 'broken' in that the plastic button has deteriorated to the point it is all cracked/torn up. I have looked online but it appears its no longer made/sold; any aftermarket sources??

I have to work this weekend so hoping to jump on this monday morning. In the meantime gonna study that schematic and fingers-crossed wont have to tear my truck apart looking for a short.

Thanks again everyone!
 
Pull out unit and check for part number and search for part number online. You will likely find it. The Schematic kind of makes it look like the switches are one unit or the headlight switch runs through it or something. Since you have physical damage to one of your switches I would look to change that out first. In my '03 the switches just snap in place so be careful when removing. Yours may be different so just look around it and pull it out carefully. May have to pry tabs out of the holes to get it to pop out. If you do not know what I mean ask and I will describe further. ;)

If you can check for the part number at the dealer even if they don't carry it you can search for it online. Also can check junk yards. The switches are not unique to the Avalanche.
 
Hi all, FINALLY got a break in between work and family stuff to tackle this.

I decided to start at the switches in the dash, the headlight switch and the cargo light/fog lamp cluster.  Removed them, tried to put in a fuse, fuse popped.

In a fit of 'i have no idea whats going on' I decided to de-rig everything and slowly re-rig it to isolate issue. Removed all bulbs, dropped headliner, removed plugs for visors, lights, sunroof, removed all bulbs from doors, took fuse panel under hood and lifted it up to trace wires. Everything appeared normal. So put switches back in, tried a fuse, it held. Rigged headliner back, fuse held. Etc.

Long story short, it's a phantom somewhere, but so far its been 4 days and all is good.

Im am going to try and track down a replacement cargo/fog switch cluster just in case but hopefully it was just a plug that was acting up somewhere in all those plugs i unplugged....

Thanks again everyone. Hope it stays 'fixed.'
 
Back
Top