How do I do a simulation for this circuit ?

[Phloks]

Please have a look at below schematic. I have built it in real life, and the result is what is expected. Low at the input gives +12V at label RX_12V. High at the input gives 0V at label RX_12V.
However, when I try to simulate the circuit I do not see the expected output. The output stays at around +12V no matter what the input is.
Can anyone please tell me how I should do a DC simulation for this schematic ?

 

 

I have tried a transient simulation with a pulse voltage source (from 0 to 3.3v, pulse length 1 second, rise and fall 1 nanosecond) which gives me a fairly constant output of +12V at RX_12V.
A DC simulation does not give me any output in the graphics at all…..

[Phloks]

P.S.
With input I mean ENABLE_TX_12V.

[w5eeg]

I think the only problem is the output MOSFET needs to be reversed so that the P-channel source is connected to the 12 volt supply.  Attaching a uSimmics schematic screenshot.

Attachments:

1. 

   ckt_in_uSimmics.png
   

[w5eeg]

My mistake, Q2 looks correct, and I had not included Q4. When included, there is the problem you described.

[w5eeg]

Maybe R10 is the problem?  I have deactivated it in the attached screenshot.

Attachments:

1. 

   ckt_2.png
   

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