Thanks... you replaced the ignition module, on some furnaces that suffices for the printed circuit card... if there is no other item with over 10 wires connected to it, then yes, that is what I was talking about when discussing the printed circuit card.
The flame sensor is just a stainless steel rod.. with an insulated base. The ignition module puts 24 volts AC into the rod, then the burner flame acts to draw off the positive aspects of the 24vac ...leaving 24volt DC in its place, which then flows back to the ignition module as 2 to 5 micro amps DC When the ignition module senses that 2 to 5 micro amps, it allows power to the gas valve.
If the flame goes out, the 2 to 5 micro amp flow ceases, and the ignition control module turns power to the gas valve off.
Causes for flame sensor failure, is a bad ground at the metal burner head, so that the 24vac current cannot flow through the flame... thus not returning a 24vold DC signal to the ignition control.
A dirty flame sensor rod will not leak 24vac into the flame.. so will fail as a flame sensor, (requires cleaning)
There is about a 10% chance at this point that you have a 'reverse polarity' issue. You may have watch this video a few times to get the concepts completely understood.
Please attach a well focused, close up photo of the wiring diagram glued inside the service panel,you can use the paper clip-icon at the right end of the toolbar at the top of this dialog box,Include a picture of the thermostat wire connections to the printed circuit board in the same area.
If there is no paper clip-icon, look for the '+attach files' link at left of your send button.
I can mark it up with trouble shooting instructions.
We can go from there.