Damn turn signal ...

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brodertr

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May 30, 2018
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Boise
My Car
73 modded convertible
So, here we go ... 1973 convertible... 

Prob: left directional light in the instrument cluster doesn’t blink. Exterior turn signal and flashers blink. 

New LED bulbs in cluster. Cleaned all the connectors/circuit board/pins in connector. Did the 9v battery test on the bulb AND on the circuit board while bulb was installed and both worked. Changed out both relays.

Re-installed the instrument cluster, plugged it in, no left turn signal in cluster. Repeat, re-install, no light.

Maybe the pin connector that plugs into cluster? Noticed the pins were numbered. Anyone have a schematic so I can test the connector? Anyone know which pin is ground and left turn signal power? And, if that’s the prob, where do I find a replacement without having to buy a whole wiring harness?

Can I live without an interior left turn signal? Sure. But don’t want to unless absolutely nightmarish to fix.

Any ideas?

 
So, here we go ... 1973 convertible... 

Prob: left directional light in the instrument cluster doesn’t blink. Exterior turn signal and flashers blink. 

New LED bulbs in cluster. Cleaned all the connectors/circuit board/pins in connector. Did the 9v battery test on the bulb AND on the circuit board while bulb was installed and both worked. Changed out both relays.

Re-installed the instrument cluster, plugged it in, no left turn signal in cluster. Repeat, re-install, no light.

Maybe the pin connector that plugs into cluster? Noticed the pins were numbered. Anyone have a schematic so I can test the connector? Anyone know which pin is ground and left turn signal power? And, if that’s the prob, where do I find a replacement without having to buy a whole wiring harness?

Can I live without an interior left turn signal? Sure. But don’t want to unless absolutely nightmarish to fix.

Any ideas?
i would say its the circuit board @ the plug

 
I don’t think you can use leds in the dash turn signals, bulbs only. LEDs can go everywhere else. I’m using leds for everything in the interior except the turn signals. Works great and can actually see the gauges.

 
Last edited by a moderator:
Dash Cluster Pin 4, for both standard and tach dash clusters, is for left hand turn signal.

 
I've used LEDs in the turn signal indicators no problem, just can't use LED for the alternator warning lamp if equipped

Sounds like your pin at the cluster could be the culprit which you can pull the plug away and bend the tang a little and/or clean it up. Could also be the printed circuit if you didn't test it all the way at the connector end and if that's no good then a Midlife hard wired cluster would be a better fix.

 
I have LEDs in my signal indicators as well - boy are they bright at night.    :cool:

I remember reading something about not using them in the signal indicators because they're be too bright, but I'm OK with it.  During the day, it's nice having them bright.

I also remember reading something about leaving one of the bulbs as a standard bulb, and that the dimmer would still work.  Well I did, and it don't.  Not sure what I did wrong, but I have to pull the whole cluster to fix the speedo cable and do some other stuff, so I'll check it out then.

 
So, here we go ... 1973 convertible... 

Prob: left directional light in the instrument cluster doesn’t blink. Exterior turn signal and flashers blink. 

New LED bulbs in cluster. Cleaned all the connectors/circuit board/pins in connector. Did the 9v battery test on the bulb AND on the circuit board while bulb was installed and both worked. Changed out both relays.

Re-installed the instrument cluster, plugged it in, no left turn signal in cluster. Repeat, re-install, no light.

Maybe the pin connector that plugs into cluster? Noticed the pins were numbered. Anyone have a schematic so I can test the connector? Anyone know which pin is ground and left turn signal power? And, if that’s the prob, where do I find a replacement without having to buy a whole wiring harness?

Can I live without an interior left turn signal? Sure. But don’t want to unless absolutely nightmarish to fix.

Any ideas?
I'll have to agree with all of these replies saying the circuit board is the culprit. I switched 

 to LED's myself and had a nightmare with trying to get all the polarities correct, checking and rechecking with a 9 volt battery, and reconnecting and connecting the board and speedo cable. :shootself:

Replaced the board, cussed at the speedo connection on, and CAREFULLY connected the power plug, and all is well. ……..And, yes, the ALT light is the regular "old school" type bulb.

 
Thx everyone. Gonna change out the circuit board and if it doesn’t work, I’ll be the guy going obliviously down the road with the left turn signal on!

 
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