3.3 volt LED will not light

[Orion]

I am having issues with a 3.3 volt led not lighting on my express.  I checked all components to make sure they are right.  Any suggestions.

[combustionmark]

Is the express working? The led might be in backwards.

[Orion]

No LED is installed correctly per silk screen on board.  I haven't went any further with installing chips and pics.  I saw a mod for 2009 time frame that ran a jumper wire from the 5V to the 3.3V regulator.  Is this still an issue?

[DonFL]

 If you are 100% sure you have the 3.3V regulator installed, what do you have voltage-wise on the 3 pins?

[tbone321]

What version ofthe LE is this?

[Orion]

This is version 5.

[RJ]

No mod is needed for a version 5 that was all changed. Do you have the 5v led lit?

RJ

[Orion]

Yes the 5V LED is working.

[RJ]

Put a meter across the led and see if you have voltage.  Might just be a bad led.

RJ

[combustionmark]

If possible, make sure you have the 3.3 volt regulator installed and not a scr. I did this once and the led did not light. I think I had channel 13 stuck on, guess where the 3.3 regulator was.

[Orion]

I measured voltage across the LED's 5V is 2.1 V and 3.3V has no power.  I took a few images of the board in case someone can see anything.  I took the heat sinks off the regulators to verify they were correct.

[arw01]

I have not looked at the assembly manual, but in your second picture, the reistors by the terminal block at the top look like they are both the same, but appear to be going two different directions.  You would have to check the assembly manual to see if you have them correct.  I found some of the pictures just aren't color accurate enough to tell for sure on the pieces I have assembled.

Alan

[Orion]

I got it.  My pictures helped me out.  The voltage regulators were in the correct spot.  But backwards according to the silk screen  .  Like my super smart engineer mentor always say's it's obvious to the casual observer. 

[n1ist]

Resistors are not polarized; they can go either way...
/mike

[arw01]

Resistors are not polarized; they can go either way...
/mike

Thank you, I did not know that.  The manuals go out of their way to state caps are not polarizes (correction SOME can be so read the manual), therefore I fretted about my directions on the resistors unnecessarily.  I will just arrange them for aesthetics then in the future.


fixed up some errors for future readers..