Flasher one flash and none

[Dug Nichols]

My '73 has an issue with the turn signal I haven't been able to diagnose / fix and haven't found a solve for via searches...

 

When engaged, the turn signal dashboard indicator light will flash once, then not flash. Meanwhile the relay is clicking and the external bulbs are firing as expected. I replaced the relay with a NOS unit, same deal. 

 

Any ideas?

[Conserv]

Common problem. Sometimes simply reversing the wires on the light solves it.

 

There are many threads that discuss this issue.

 

Regards,

 

Steve

 

 

[Mike Self]

PM me if you'd like a column I did on the subject.  It's generally the contact points inside the flasher relay that cause the problem, presuming all the outside lights are equally bright (and thus are getting their full ration of volts).

 

mike

[John76]

Check all the ground points, even on the hazard flasher button.

 

[yeewiz]

Would adding LED taillights cause this problem?  I have the same issue.  I swear it only started after I replaced my original taillights with a LED kit.

[Son of Marty]

Yes led's do cause this they are much lower draw than incessant bulbs and the flasher interprets this as a bulb that's burned out. You'll need to add a resistor or go to a electronic flasher to make the indicator work.

[yeewiz]

4 hours ago, Son of Marty said:

 You'll need to add a resistor or go to a electronic flasher to make the indicator work.

Ok, thanks SOM.  Looks like the electronic flasher, EL-13, is the go-to solution, though it seems some have had problems with it.  Ok,  time to hunker down with the threads and get my hands dirty.   

[Mike Self]

11 hours ago, yeewiz said:

You'll need to add a resistor

OK, all you younger-than-me electronics-savvy guys/gals:  if I wanted to interpose a plain ole resistor at each of the four turn signal bulb sockets in order to use an LED bulb with the original flasher, what value (ohms & watts) resistor would I use?  Automotive electrical systems I know; electronics, not so much.  

 

TIA

 

mike

[MurphinDC]

On 3/20/2022 at 11:54 AM, otto said:

My '73 has an issue with the turn signal I haven't been able to diagnose / fix and haven't found a solve for via searches...

 

When engaged, the turn signal dashboard indicator light will flash once, then not flash. Meanwhile the relay is clicking and the external bulbs are firing as expected. I replaced the relay with a NOS unit, same deal. 

 

Any ideas?

As noted, check your grounds.  My rear lights ground needed a cleaning and that resolved my issue.  Good luck!

[tzei]

I had the same issue. Groved to accept it as a part of the cars personality.

[John76]

On 3/20/2022 at 8:33 PM, yeewiz said:

Looks like the electronic flasher, EL-13, is the go-to solution,

The EL-13 electronic flasher is for use with 4 regular 21W incandescent turn signal bulbs. 

X pin to +12V (Green/violet)

P pin to the dash indicator light (Black/white)

L pin to the 4 x 21W bulbs (Green/yellow)

The stock Brown wire (ground) is not used.

 

The EL-13A1 flasher is used with 4 LED bulbs, such as the Sirius LED type 1157.

 

John

 

[yeewiz]

11 hours ago, John76 said:

The EL-13A1 flasher is used with 4 LED bulbs, such as the Sirius LED type 1157.

 

John

 

 

So, if my front turn bulbs are incandescent, but my rear turns are LED, what do you think?

[golf02]

Not to add another level of confusion, but I had a similar problem and the hazard switch was flaking out on me, took it apart, cleaned it and problem disappeared, other thing to note, the front grounding on the turn signals is through the tiny screws that hold the housing to the body. They always rust I put dedicated ground wires from the front turn signal housings to the body as standard repairs.

[Son of Marty]

Golf02, the short answer is yes, the t/s blinker will read the 2 leds as low resistance = bulb out.

[Tommy]

On 3/21/2022 at 5:25 PM, Mike Self said:

OK, all you younger-than-me electronics-savvy guys/gals:  if I wanted to interpose a plain ole resistor at each of the four turn signal bulb sockets in order to use an LED bulb with the original flasher, what value (ohms & watts) resistor would I use?  Automotive electrical systems I know; electronics, not so much.  

 

TIA

 

mike

The flasher bulbs are 21W. They draw current I=P/U=21W/12V=1,75A. I don't know how much a led bulb pulls, but very little. To restore the current resistance would have to be R=U/I=6,86ohms. Flasher bulb was 21W, so the resistor would have to dissipate the same power. That is a lot. Typical little resistor you see in electronic devices can handle 0,6W.

 

Since leds take some and all the starting values are inaccurate, let's say 8ohms might work. With google I could find these.

5 Pcs Wire Wound Ceramic Cement Resistor 8 Ohm 20W 5%

WWW.EBAY.COM

---

5 X Ceramic Resistor 20W, 8 ohm( Ω). Power : 20W. 5 X20W, 8 ohm Resistors. Resistance : 8Ω. : 0.7mm / 0.027". We have good "Pro-sales service" system. Body Size (Approx.). : 61 x 12 x 13mm/2.4" x 0.47" x 0.51" (L W H).

Pretty bulky, I would say. As a flasher is not powered continously, maybe 10W resistor would work. But it will get hot and need to be positioned accordingly to avoid stuff melting around. 

I have decided to stick with incandescent bulbs.