Directional signal and hazard warning light

[James Stein]

 2002 manufactured April 29, 1971. Directional signals work, indicator light on display illuminate only 1 time each direction when activate stalk but can hear them blinking. Hazard lights work and display keeps illuminating. Any advice appreciated. 

[John76]

James,

You might have a bad turn signal flasher unit.

 

Not sure if your '71 has the same circuit as my '76, but I had the same problem. Mine came with a Hella TB826 flasher unit located under the dash next to the hood release lever.  The capacitor in the Hella unit usually dies of old age (like us all) and fails to send a flashing signal to the dash light.

Check if your wiring harness has these 4 wires:

(1) Green/Violet is +12V. 

(2) Green/Yellow for the bulbs (load).

(3) Brown is ground.  

(4) Black/White for the instrument panel indicator light.

 

A nice upgrade is an electronic flasher. I used a NAPA EL-13 (cheap!) with only 3 terminals (X, P &L).The brown ground wire is not used.

I connected the "X" terminal to the green/violet wire for +12V.

The "P" terminal is connected to the black/white wire to the instrument panel.

The "L" terminal is connected to the green/yellow wire for the outside lights (load)

The remaining brown ground wire is not used.

 

Disclaimer....I have heard others say this upgrade may not work on all cars, and could require a different NAPA part number.

Make sure all your turn signal bulbs are identical. Miss-matched bulbs could confuse the electronic flasher???

 

John

 

[Henning]

This is a very common issue. Check for proper electrical connections wherever you can find, especially grounds. The indicator works in dependence of the load. So if there's a loss of load it won't work. It works once when the signals are activated because the cold bulbs draw more current than warm ones.

I remember a 72 roundie I owned some years ago that I converted to square lights because it was rear-ended (I didn't have a roundie tail panel). Before, the indicator worked like yours and after, it worked like it should. I think it is because square lights have better ground connections without this cinc-press-cast housing. My idea.

 

hen

 

[Mike Self]

Once you've determined that all four lamps flash with equal brilliance, that'll tell you that the problem isn't a ground or bulb socket contact problem.  

 

You (probably) need to delve into the flasher unit's innards.  If you can't find a writeup in the archives on how to tweak the set of points inside the flasher box that makes the dash light blink, PM me and I'll send you a column I did on solving the problem.  It's actually a pretty easy fix, just a little fiddly.  But worth it.

 

mike

[James Stein]

Thank you for the replies.

[AustrianVespaGuy]

OR, this can also happen if you've replaced any of the indicator bulbs with LED ones. . . worth asking!

[Eissmann]

My "B" Light would not blink, although the blinkers worked as they should. I tried opening the flasher unit and found that mine is a different unit than the one shown above. It has a different part number (Hella 89 6756 000) and I couldn't get the points to work properly. Maybe it is a worn out replacement.  

I replaced it with a Napa EL13 per JOhn76's instructions and the dash light is working perfectly! Thanks John76!