LED Dash Lights

[FJRdoc]

I'm in the process of restoring my 1970 Duster 340 dash assembly. The instrument cluster is finished and on the table. I purchased LED lights for the dash and I understand that they won't work if the polarity is incorrect.
How can I bench test each light to make sure that I have them installed with the correct polarity?

 

[Captain Chaos]

I had that issue on some led lights for an aftermarket motorcycle cluster. Should be able to put power to the cluster and see what lights up.

 

[RedFish]

These printed circuit boards are simple. If you can get the rabbit to the Trix on the back of a cereal box you can interpret these boards. So attach a ground the instrument housing and apply 12 volts to the individual contact posts routed to each bulb socket. If the LED doesn't come on, rotate its polarity.
I'll go ahead and tell you... these bulbs don't make a dependable connection in our OEM sockets. They may work fine on the work bench and stop working with a bump in the road.
Good luck with them.

 

[j-miller]

Just like the previous poster's said.

What part of Lancaster you in FJRdoc?

 

[RedFish]

OOPs I guess I should mention the one bulb that will need both positive and ground on those contact posts it the brake indicator bulb. It doesn't use chassis ground of the housing. The switch on the park brake mechanism supplies its ground.

 

[cudajim]

LED's are diodes by definition so they only conduct one way. I'm sticking with my good old (AC or DC) light bulbs.

 

[68gtxman]

Don't think you can dim LEDs either.