Need Help With Transistor Logic Circuit Design

Greetings all and Happy New Year!

I've been working on a logic circuit to control the main entrance gate at our ranch for some time now. I've been testing using Falstad's Circuit Simulator.

However, I've run into a problem: In the control head, I need to implement some simple logic to turn on the "STOPPED" indicator when the main entrance gate is not at the open limit (open limit = NOT grounded) AND not at the closed limit (closed limit = NOT grounded), OR when the "STOP" button is pressed (sending 12V to the latch interrupt relay).

I'm going to admit right up front that I have very little electronics knowledge compared to most people out here, but that hasn't stopped me from trying - smiles.

Let me post what I have first, and then I will explain the dilemma:

In the above schematic, I can see the Q3 transistor is forward biased even when all inputs are zero, and I fail to understand why.

I'm also not sure if I have the saturation points set correctly.

And lastly, not matter what I do, I cannot make the current draw of the LED equal to exactly 10 mA in all scenarios - it's close, but I'd like to know if there is a solution where it is always exactly 10 mA.

It DOES work....just not perfectly. Q1, Q2, and Q3 are all 100 hFE transistors, and power consumption is a factor since this is all solar powered.

Appreciate any help on this.

I'm really interested in other's thoughts and ideas as I am sure there is more than a couple of solutions to this problem.

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AnalogKid nailed it. Can't thank you enough.

Answer

Your original circuit, updated for more stable operation. Also, eliminated Q3.

^{simulate this circuit – Schematic created using CircuitLab}