Weigh scale with buzzer

daveyg1987:
unloaded I get 4.21v at both A+ and A- and with 24lbs on it I am still getting 4.21v and 4.21v

Something is very wrong. Both A+ and A- should be about half of E+, with and without load. For example, at no load, both should be 2.1v. At the load cell's rated load, there should be at most 20mV between A+ and A- (using the default gain); for example, 2.110v and 2.090v (whether that can be achieved depends on the load cell's sensitivity).

Check your wiring. Post photos of your wiring.

Also, there's no point in measuring the voltage of CLK and DT - they're digital pins.

Here's my wiring currently. My new load cells and HX711 should be here Friday.
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It looks like black is going to E+ and red is going to E-. It's usually the other way around. But that shouldn't be the source of your problem.

If there is no connection between E- and the load cell, then you'd get the E+ voltage at A+ and A-. Due to the fuzzy photo, it's hard to judge the soldering, but the connection to E- looks ok, so that's probably not the problem. FWIW, the joint E+ doesn't look all that great, but it's hard to tell.

I guess my next step would be to disconnect the load cell from the HX711 and measure the resistances between all wires... black to red, white to green, and between the other four pairs.

Just out of curiosity, while the load cell is disconnected, measure A+ and A- relative to ground again. If they're at E+ (unlikely, but you never know...), the board is NG.

And, with the load cell disconnected from the HX711, apply 5v to red and black using a phone charger and measure the voltage at A+ and A- no load and with load, relative to ground and to each other.

Dave, good catch on the red/black swap, I had it soldered the other way before taking this picture but when I went to take the pic, I lifted the HX711 and those two actually broke the wire, leaving a little frayed wire soldered to the boards, so I quickly reattached and took the photo, but I apparently swapped them in my haste. I will desolder the load cell today and check resistances and check the board as you have suggested.

daveyg1987:
good catch on the red/black swap

is not a big deal, but this...

daveyg1987:
...I lifted the HX711 and those two actually broke the wire...

...makes it sound like there may have been a bad connection. If there was no continuity at E-, then that could explain your problem.