Sign up to remove ads. We'd love to have you amongst our ranks! Just Click here!


gmc forums   gmc forums


Go Back   GMC Forums > GMC Vehicles Currently In Production > GMC Sierra Forum

Advertisements
cars connected social network






Notices

GMC Sierra Forum Forum for discussions regarding the GMC Sierra


GMC Forum: 2011 Sierra signal issue
Reply
 
Thread Tools
  #1  
Old 07-27-2018, 04:59 PM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default 2011 Sierra signal issue

I have 2011 Sierra SLE (?) Ext. Cab 4x4. the left side signal started rapid firing. When I checked the bulbs I noticed that besides flashing faster than normal that the bulbs were dim & the back up light was also flashing. i'm thinking that there must be a short somewhere in the harness, possibly in the trailer light loom. anyone seen this before or want to hazard a guess as to where to start looking??
Reply With Quote

  #2  
Old 08-01-2018, 10:23 PM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default

in addition to the above I've noticed that the dome lights do not work when the doors open but DO work when switched on manually with the dash switch or the switches at the lights. and the left taillight burns dimly.
Reply With Quote
  #3  
Old 08-05-2018, 06:03 PM
mogleybear mogleybear is offline
Senior Member
Drives a 2012 GMC Sierra 1500 Crew Cab
 
Join Date: Feb 2013
Location: Jemez Mountains
Posts: 216
Default

Sorry your not getting any replies. I haven't seen this issue, so I can't suggest anything other than maybe the bulb that burned out is somehow shorting the system. Like I said, I haven't seen that before. First thing I would try is cleaning all the connections to the lights affected.
Reply With Quote
  #4  
Old 08-05-2018, 06:37 PM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default

while trying to deal this signal issue I pulled the fuse panel cover off of the left end of the dash. there's a really thin ( maybe 18 gauge. ) that's attached to a screw in the dash & appears to be a ground wire. the other end is not connected to anything. any idea where this is supposed to be connected? might this be related??

I haven't had the time to deal with this yet & I've not found a meter to borrow. I do have a continuity test light that I used to use to static set points & timing ( yeah i'm old ). AND it's just been too hot out. there are no burned out bulbs. I am going to try unplugging the trailer light pigtail to isolate that & go from there. wiring issues can be a real P.I.T.A. to diagnose which can really run up the hours if I have to put the truck in a shop.
I miss my older trucks. when you opened the hood you could actually see the engine! to me all this electronic cr*p is not an improvement. I had an 83 ford truck with an inline 300 6 cylinder & a carburetor that got 18 M.P.G city & 21 M.P.G. highway. I also had the same engine in a 1990 ford with computerized E.F.I that got 13 M.P.G. city & highway no matter how I drove it. 1960's volvos got 28 M.P.G with carbs & points & 32 M.P.G at 80 M.P.H. on the models that had overdrive trannies. and anyone with decent set of common tools & 1/2 a brain could fix em'!
rants over

Last edited by rober; 08-05-2018 at 07:07 PM.
Reply With Quote
  #5  
Old 08-05-2018, 08:49 PM
mogleybear mogleybear is offline
Senior Member
Drives a 2012 GMC Sierra 1500 Crew Cab
 
Join Date: Feb 2013
Location: Jemez Mountains
Posts: 216
Default

I feel your pain. Yes, a broken ground connection could be related. Unfortunately I don't know where it might be connected. When I get a chance I will look at my truck and see if I can see any wire like that. Who knows, GM has gotten really cheap and for some reason they seem to think using thin and shorter wire is a good thing. Saves about a tenth of a cent per truck, but frustrates the crap out of the owner.
Reply With Quote
  #6  
Old 08-09-2018, 04:36 PM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default

this just keeps getting better. I disconnected the trailer light harness. no change. removed taillight & removed bulbs one at a time. still rapid flashing but got brighter without the backup light bulb. now for the good part. decided I change the flasher just for grins. turned the signal on & listened & it sounds like the flasher clicks are being broadcast thru the driver's side speaker!! now how weird is that??
Reply With Quote
  #7  
Old 08-09-2018, 06:24 PM
mogleybear mogleybear is offline
Senior Member
Drives a 2012 GMC Sierra 1500 Crew Cab
 
Join Date: Feb 2013
Location: Jemez Mountains
Posts: 216
Default

Definitely strange. Now that I think about it, I had an 88 Chevy that did the fast flash. I don't know about the reverse lights flashing with it though (all lights were working). If I remember right all I did was replace all the tail / brake light bulbs on that side and cleaned all the connections at the tail light.

I did look at my truck, a kind of quick look though, but I didn't see any thin wire. I will look more closely though and see if I can see anything. Is the wire behind the fuse panel cover or under the dash?
Reply With Quote
  #8  
Old 08-09-2018, 06:39 PM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default

the mystery wire is under the fuse panel cover. it is attached to the dash via a screw so it appears to be a ground lead. it was run into the dash area just above the fuse panel & is 2' long. it appears to be broken.

there is a lever switch on the front edge of both of the rear doors for the extd. cab. are these the dome light switches. a friend at the local body shops says they might be for the door ajar alarms.

I found this on you tune an hour ago. it's given me some hope. I'll check it out in the morning.
https://www.youtube.com/watch?v=Vxx3vkfMzgs
Reply With Quote
  #9  
Old 08-10-2018, 10:34 AM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default

tried unplugging & cleaning the terminals in the video.

also noticed that the left signal flashes normally when I use the 4 way hazards.

where is the flasher??
Reply With Quote
  #10  
Old 08-10-2018, 12:44 PM
rober rober is offline
Junior Member
Drives a GMC Truck
 
Join Date: Jul 2018
Posts: 8
Default

well I got a wild hair & pulled those connecting plugs again as shown in the video only this time I had my cheaters on & hooked up a drop light. the top connector which is the one that feed the driver's side taillight looked like it had clear silicone in it. after probing it it appeared to be some type of clear grease. I sprayed it with electric motor cleaner & blew it out with air. this time it cured the problem!!! downside is that each fitting has a neoprene-like gasket & the top & bottom connectors would not snap into a locked position with the gaskets in place. I 'll deal with that shortly but for now the light is working.

it looks like the dome light issue is coincidental & not related as it is still not
working. i'll try tracking fuses 1st since they do not work with either door.
research looks like the switch on the rear doors are far the door ajar alert & the dome light switches are tied in with the door locks.

AND there is no flasher. it's controlled by the BCM AND the alert chimes & the signal clicking are simulated thru the driver's side speaker.
I think I'm going to start shopping for a clean late 70's to mid 80's truck.
Reply With Quote
Reply
Registered members see less ads. Please sign up! We'd love to have you...

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 07:54 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
gmcowners.com recognizes that "GMC", it's logos and various model names and numbers are registered trademarks of the General Motors Corporation. These terms are used for identification purposes only. gmcowners.com is not affiliated in any way with the General Motors Corporation, GMC or any other company listed herein. All information on this site is the opinion of its members and not the opinion of the site itself. ©2017 Madison Ross Media Group. All rights reserved. Content published on GMCOwners.com requires permission for reprint.


MADISON ROSS MEDIA GROUP MARKETPLACE
Need products for your GMC Truck? Check out your options at the links below:

Looking for something a little sporty? Believe it or not, Kia may have something for you. The Kia Stinger is a large sport-oriented hatchback sedan in the mold of the Audi A7.