pic: What's weird with this image

[Tom Line]

I bet one of the leds is burned out. We have a similar issue, but ours is always green on an old one. Does that one ever turn green?

[Jonathan L.]

Originally Posted by Tom Line

I bet one of the leds is burned out. We have a similar issue, but ours is always green on an old one. Does that one ever turn green?

This is always backward of what the signal is. When we say forward, it turns red; When we say backward, it turns green.

[JamesBrown]

Originally Posted by Kevin Sevcik

That's a more remote possibility, but possibly true. Unless you have the exact same motors wired the exact same way, they might still turn differently. If a multimeter reads the same voltage when you put the red probe on M+ and the black probe on M-, then I would definitely agree with your assessment.

If it is bad internal LED wiring and the Talon is new, I would talk with Vex, Andymark, Cross the Road, or FIRST about getting a replacement. That LED is valuable for troubleshooting, and if all the fault codes are in flashing green, that's going to be extremely confusing.

Originally Posted by Jonathan L.

This is always backward of what the signal is. When we say forward, it turns red; When we say backward, it turns green.

Seems entirely plausible to me that the LED was simply installed backwards. Bi Color LEDs are (usually at least) 3 pin, with the center being the common Cathode, and pins 1 and 3 being the two different anodes. It would be a pretty simple mistake to install the LED 180 degrees out and have the colors reversed.

[ratdude747]

Originally Posted by JamesBrown

Seems entirely plausible to me that the LED was simply installed backwards. Bi Color LEDs are (usually at least) 3 pin, with the center being the common Cathode, and pins 1 and 3 being the two different anodes. It would be a pretty simple mistake to install the LED 180 degrees out and have the colors reversed.

No, actually they do make two pin bi-color LEDs. The color is determined by the direction of current (so the anode of one color is the cathode of the other and vice versa). IIRC this used to be and still may be common, as they are particularly useful for driver circuits involving OP-AMP voltage comparitors; they still work for digital circuits too (if run between two outputs, one used to source, one used to sink).

That said, once again, a backwards LED would still have the same result. However, I'd think these were machine assembled which would mean that the error would have to be with the component itself (either in the reel tape backwards or somehow assembled wrong at the LED fab).

Either way, I'd consider that to be DOA and grounds for a warranty exchange.