Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   PeachParts Mercedes-Benz Forum > Mercedes-Benz Tech Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 07-25-2008, 02:11 PM
Registered User
 
Join Date: Jun 2008
Posts: 9
Defective Lamp Indicator on Instrument Cluster stays on

When I start my 300D and turn on the headlights, the defective lamp indicator turns on. I have been told that an improper bulb could have been installed causing a change in resistance thus triggering the indicator lamp. I don't think this is the cause. Is there a relay that controls the defective lamp indicator that could have become defective?

Reply With Quote
  #2  
Old 07-25-2008, 02:25 PM
Registered User
 
Join Date: Feb 2004
Location: Walnut Creek, CA & 1,150 miles S of Key West
Posts: 4,874
Have you checked license plate bulbs, rear fog bulb and all marker lights?
__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)
Reply With Quote
  #3  
Old 07-25-2008, 02:51 PM
865sp300e's Avatar
Talent Scout
 
Join Date: Feb 2005
Location: Yardley, PA
Posts: 318
Incorrect bulbs can cause this issue, as suggested check all bulbs. The license plate lights and rear window brake light is often overlooked.
__________________
'86 300E 5 speed
'71 Triumph TR6
'46 Cushman Scooter
'41 Ford 9N tractor
Reply With Quote
  #4  
Old 07-25-2008, 04:56 PM
Registered User
 
Join Date: Jun 2008
Posts: 9
Lamps have been checked

Yes, I have checked all lamps including license plate, fog, and running. I am stumped. I have heard there is a multiple pin relay that checks the resistance and triggers the warning lamp if there is a discrepancy. I would like to locate this relay and just for kicks replace it from one of my other 300's.

Do you where this relay is located?

Thanks.
Reply With Quote
  #5  
Old 07-25-2008, 05:38 PM
G-Benz's Avatar
Razorback Soccer Dad
 
Join Date: Apr 2001
Location: Dallas/Fort-Worth
Posts: 5,711
I have posted this several times, but what the heck:

When you remove the inner taillight covers to gain access to the bulbs, you will notice two metal strips that run lengthwise. These can loosen due to vibration over time and throw off ground contact with some of the bulbs, generally the double-filament ones...they appear to be dim.

If you press a finger against the metal strip next to one of those bulbs and notice that the bulb illumination changes intensity (i.e., gets brighter), then you've hit on your problem. You can probably look at your dash indicator from back at the trunk and notice that the indicator has gone off.

Continue to press along the metal strip...you should hear faint "snaps" where it reseats. Problem solved...hopefully.
__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car
Reply With Quote
  #6  
Old 07-26-2008, 04:05 PM
ps2cho's Avatar
Registered User
 
Join Date: Jun 2006
Location: Chandler, Arizona
Posts: 3,525
^ I'll give the bulb trick a try tonight. I am having the exact same problem in my TE. Replaced all bulbs and it just stays on all the time when the lights are turned on.

I'll let you know if I have any luck with that.
__________________
2016 Monsoon Gray Audi Allroad - 21k
2008 Black Mercedes E350 4Matic Sport - 131k
2014 Jeep Wranger Unlimited Sahara - 62k
2003 Gray Mercedes ML350 - 122k
Reply With Quote
  #7  
Old 07-26-2008, 04:52 PM
Registered User
 
Join Date: Feb 2004
Location: Walnut Creek, CA & 1,150 miles S of Key West
Posts: 4,874
Additionally, as I understand the system reads differences in resistance. A US vs OEM bulb will measure differently. Replacement in pairs may help.
__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)
Reply With Quote
  #8  
Old 07-28-2008, 05:19 PM
Registered User
 
Join Date: Mar 2007
Location: Houston, Texas
Posts: 211
Corrosion also can cause a lower than spec measurement.....check for any dimmer lights and run a piece of fine sandpaper over the connectors....mine was acting up and it was a slightly corroded bulb socket....took me forever to find!

Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -4. The time now is 06:53 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page