Tail Ligths/brakes/reverse on 97 GMC truck - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Electrical
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 04-04-2011, 10:21 AM
jjupiter100's Avatar
Registered User
 
Last photo:
Join Date: Nov 2009
Location: Arlington
Posts: 44
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Tail Ligths/brakes/reverse on 97 GMC truck

Not that this is necessarily related to my other post about my rearview mirror, but my turn signals and brake lights have been on the fritz for the past year also. Started with the driver side. Blinker blinks real quickly and left brake light wouldn't light up when lights were on. Fixed a couple loose connections by spare tire under the bed, but never could get it to work properly. All bulbs are good. So I was thinking it might be the circuit board housed in the tailight housing. Some connections look kinda old. Then, about 2 months ago the passenger side started doing the same thing. Neither reverse light works either.
I don't want to just throw some new parts at it. I'm thinking of just taking it to a mechanic to fix because inspection is due in may, and it ain't gonna pass the way it is now (usually has trouble passing anyways).

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 04-04-2011, 01:53 PM
Registered User
 
Join Date: Dec 2005
Location: Madison, S.D.
Posts: 129
Wiki Edits: 0

Thanks: 0
Thanked 6 Times in 4 Posts
Check your ground staps from frame to bed. They get rusty and crudded up.Or broken.
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 04-04-2011, 03:29 PM
EOD Guy's Avatar
Registered User
 
Last photo:
Join Date: Aug 2010
Location: Alabama
Posts: 2,099
Wiki Edits: 0

Thanks: 1
Thanked 140 Times in 131 Posts
Groiunds seem like a possibility
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 04-04-2011, 07:26 PM
Registered User
 
Join Date: Sep 2007
Location: In The Garage
Posts: 334
Wiki Edits: 0

Thanks: 3
Thanked 6 Times in 6 Posts
Jjupiter, does your 97 have a multifunction switch that
controls the turn signals, dimmer, windshield wipers, all
in one? If so, I think that's your problem.

These switches are extremely easy to replace, at a cost
of $40-60....
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 04-05-2011, 05:44 AM
jjupiter100's Avatar
Registered User
 
Last photo:
Join Date: Nov 2009
Location: Arlington
Posts: 44
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
seems like grounding out might be an issue. i've got several electrical gremlins right now.

Runnin'OnEmpty - by multi function switch, are you referring to the turn signal stalk? If so, then yes my truck has one. It controls: turn signals, wiper blades, hi/lo beams, and cruise control (which has never worked since I bought the truck 10 years ago).
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 04-05-2011, 02:27 PM
Registered User
 
Join Date: Sep 2007
Location: In The Garage
Posts: 334
Wiki Edits: 0

Thanks: 3
Thanked 6 Times in 6 Posts
Yes, that's the MFS (multifuction switch).
There's a good chance the MFS is faulty and
causing the turn signal problems. The brake
light circuitry also runs through this switch.

I suspect the back-up lights are a separate
problem.......Probably in the switch located
on the transmission or shift linkage.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 04-05-2011, 02:52 PM
jjupiter100's Avatar
Registered User
 
Last photo:
Join Date: Nov 2009
Location: Arlington
Posts: 44
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
do you think it would have anything to do with my light indicator on the dash not illuminating what gear i'm in? not even sure if that little red thing is a light or what, but it's probably been gone about the same amount of time as i've been having these other problems. it's in the dash cluster under the speedo.
i just have to listen/feel what gear i've put it into P R N D 1 2
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 04-05-2011, 03:09 PM
Registered User
 
Last photo:
Join Date: Nov 2010
Location: Calgary,Alberta,Canada
Posts: 230
Wiki Edits: 0

Thanks: 0
Thanked 10 Times in 9 Posts
rear lights

before you go buyin stuff,
first check the trailer plug if equipped. sometimes they can cause you grief, especially if they are wet. walmart sells a little thing you can plug in to the trailer plug, it has led's on it and that will tell you what you have powered up there.
unplug the harness under the rear of the box and do a test with a testlight on each circuit. power up the tail lights, signals and back up one at a time . use the testlight ground on the frame of the truck, then if it all checks out, plug it back in and go to the light plug in. do it all over again there. if it checks out good there then it is probably the bulb holder that screws onto the back of the light. if you have the lights on and the test light powers up on the ground wire, then you don't have a good ground. all it takes is a bad ground and the power from the powered up circuit will go through the bulb to the bulb ground, then back through the element of the other circuit in the bulb (dual element bulb) and try to ground through the other circuit.if it makes a ground through the other circuit then usually that bulb will be dim. if in doubt, leave everything connected and turn on a signal. then go back to the light and, with a test wire that is connected to ground, touch the metal part of the buld (that's the ground part) or if you have the push in style bulbs, touch the ground circuit for that bulb. see what happens. if it lights up like it should, then you have a bad ground for that light. i have found that most of the light issues with those trucks comes from the bulb holder on the back side of the light. they have a bad connection to the bulb or bad ground circuit in the bulb holder part. if you do the test at the plug under the rear of the truck and find everything works properly there then the problem lies after that.
have fun...
dsraven
Reply With Quote Quick reply to this message

Recent Electrical posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
can i fit a th350'c' tail and shaft to a 700-r4 truck cased trans? nobler Transmission - Rearend 1 03-22-2011 06:36 PM
67 GMC 3/4 ton truck brakes kandyman Suspension - Brakes - Steering 3 06-14-2010 09:20 AM
Custom LED tail ligths, how to bundle led's? Augusto Electrical 3 03-03-2009 12:30 PM
No Reverse..ford truck 5 speed transmition MAYNARDTRUCKIN Transmission - Rearend 1 07-17-2007 07:17 PM
ideas for reverse lights - '65 chevy truck Woogeroo Electrical 2 12-08-2005 05:48 PM


All times are GMT -6. The time now is 09:51 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.