Turn Signal Flasher Reconstruction - Mercedes-Benz Forum

LinkBack Thread Tools Display Modes
post #1 of 5 (permalink) Old 02-27-2012, 09:05 AM Thread Starter
BenzWorld Senior Member
ejboyd5's Avatar
Date registered: Jun 2009
Vehicle: 1955 300 SL
Location: Southold, NY
Posts: 440
Mentioned: 0 Post(s)
Quoted: 97 Post(s)
(Thread Starter)
Turn Signal Flasher Reconstruction

Suddenly, the turn signal flasher unit in my 1955 Coupe stopped working.

Failed electromechanical turn signal flasher

A slightly premature post-mortem examination revealed that a tiny spring supplying proper placement for one of the bimetallic strips had collapsed rendering the unit inoperative. An adjustable harness made from fine wire restored operability, but with a slightly different flashing cadence than previously.

Electromechanical flasher with fine wire spring

Several weeks later the unit stopped working again making it the obvious time for a more permanent solution, but this was complicated by the fact that the original flasher unit had been substituted by the first owner of the car (sometime prior to 1964) and that I did not wish to disturb the somewhat fragile wiring harness so as to return to the original configuration. Hence, I was faced with the task of adapting a modern flasher unit to fit within the existing canister to mate up with the female connecter as installed on the harness.

Several trials with modern flasher units (I didn’t realize there were so many) resulted in no activity whatsoever, the blowing of No.5 fuse, or an unacceptably rapid flashing rate depending on how the wires were connected. Research indicated that these units all had a “bulb out” sensing circuit that would produce a rapid flash to indicate an inoperative bulb and that the load created by the Coupe’s standard two bulb system was not sufficient to overcome this modern day safety device.

Research on the Internet revealed www.autolumination.com Tail Light Brake Light Turn Signal LED Bulbs which advertised an EP34 (CF13JL-02) unit sporting the proper electrical connections and designed to restore a proper flash rate regardless of incandescent or LED bulb use or any mixture thereof. $14.99 plus $4.00 shipping plus four day delivery time from Arizona provided me with a generic appearing flasher labeled only “0431” which when temporarily wired into the car worked perfectly.

Electronic flasher with steady flash rate for incandescent and LED bulbs

To provide the proper connection to the existing wiring, I dismembered a standard Mercedes-Benz relay (001 542 02 19) and soldered wires to the appropriate pins to provide the needed “B” (+), “E” (-) and “L” (Load) connections. Since there would be insufficient room within the old canister to allow use of push on wire connectors, the flat spades on the flasher unit were drilled and tapped for 6-32 screws and the wires attached accordingly. A new base plate was fabricated from sheet plastic to mount the reconfigured relay base and to seal the bottom of the canister. This base plate was attached to the relay base using ethyl cyanoacrylate glue.

Flasher on the left and “donor” MB relay on he right with the proper base pin configuration.

Relay base with wires attached, the electronic flasher with tapped holes and screws, and the round baseplate to fit the electromechanical flasher can.

The electronic flasher wired to the “donor” base with the round baseplate attached.

Finally, to eliminate any chance of shorting caused by internal movement, all connections were covered with Liquid Electrical Tape and the inside of the canister was insulated with a portion of the central cardboard tube from a roll of toilet paper (several attempts were required here as these tubes come in slightly different diameters). The completed assembly was installed in the canister using clear silicone as an adhesive/sealer resulting in a unit visually identical to that with which I began, but one that functioned as intended.

Assembled replacement flasher with insulation applied to the internal connections.

Assembled flasher contains state of the art electronic flasher with no change in appearance from the electromechanical flasher.
ejboyd5 is offline  
Sponsored Links
post #2 of 5 (permalink) Old 02-27-2012, 09:33 AM
BenzWorld Veteran
Date registered: Nov 2008
Vehicle: 1981 300TD 310k--1966 230 165k--1970 280se 172k
Location: Ohio City, Ohio
Posts: 636
Mentioned: 1 Post(s)
Quoted: 37 Post(s)
Thanks for posting this. I love these types of workarounds.

1981 300TD--310k miles
1970 280sel--172k miles
1966 230--162k miles
carpenterman is offline  
post #3 of 5 (permalink) Old 02-27-2012, 07:29 PM
BenzWorld Elite
DirectLA's Avatar
Date registered: Jan 2007
Vehicle: 1962 W111 220SE Coupe
Location: Cloud City, OR
Posts: 2,289
Mentioned: 1 Post(s)
Quoted: 8 Post(s)
Agreed, and better still that it still appears "vintage" even if not original. cool!


The Coupe Group (W111/112 coupes and cabs)official website
The Coupe Group on Facebook

"Too many people are working at jobs they hate, to buy things they don't particularly want, to impress people they don't even care about." --Dr. Deepak Chopra
DirectLA is offline  
post #4 of 5 (permalink) Old 02-28-2012, 09:12 AM
BenzWorld Senior Member
Date registered: May 2007
Vehicle: 64' 220SEc, 72' 300SEL 6.3, lots of parts
Location: San Diego/Spring Valley
Posts: 512
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
I like that fix

That fix needs to be done and made available to the other many owners of these cars, can I suggest making them available thru the parts professionals also.
I have some old blinkers saved for core parts.

Brian O
bostosh is offline  
post #5 of 5 (permalink) Old 02-29-2012, 12:16 AM
BenzWorld Elite
Grubeguy's Avatar
Date registered: Jan 2006
Vehicle: 73 280SE 4.5, 71 300SEL, 03 BMW Z4, 72 Fiat 850, 80 Triumph TR7, 85 Porsche 911
Location: DC Area
Posts: 2,137
Mentioned: 1 Post(s)
Quoted: 104 Post(s)
Send a message via MSN to Grubeguy Send a message via Yahoo to Grubeguy
The Mercedes Gods are gonna' die! But not me - I love this kind of stuff! Well done!
Grubeguy is offline  
Sponsored Links

  Mercedes-Benz Forum > General Mercedes-Benz Forums > Vintage Mercedes-Benz

Quick Reply

Register Now

In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


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
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Topic Author Forum Replies Last Post
turn signal flasher casinogoer Vintage Mercedes-Benz 1 10-19-2011 08:53 AM
LED turn signal/flasher relay mogish Unimog 98 07-05-2011 06:19 PM
No turn signal/flasher zumwoll W123 E,CE,D,CD,TD,TE Class 4 01-01-2007 12:23 PM
Turn signal flasher Sfak G-Class 2 04-22-2004 07:19 AM
Turn signal flasher Nate W201 190-Class 0 09-14-2002 08:14 AM

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


Title goes here

video goes here
description goes here. Read Full Story
For the best viewing experience please update your browser to Google Chrome