Code p 1684 on 2002 town and county - 2002 Chrysler Town & Country

https://www.modifiedlife.com/2007-chrysler-town-and-country-stereo-wiring-chart/

Your vehicle computer thinks your vehicle is broken, and your vehicle computer cannot be reprogrammed to think differently.
Some people would stick a short piece of black electrical tape over the light on the dash if it bothered them too much.

Trans control system malfunction. The transmission control module is bad. How to Replace The Transmission Control Module in 2002 Dodge Grand Caravan...

P1684 - the battery has been disconnected within the last 50 starts , pretty much harmless, maybe it's time for new battery or check battery terminal connection.
P0123- throttle position sensor high input - probably broken sensor or wire, mechanic has to check it, engine has rough/high idle
P0118 - Engine Coolant Temperature Circuit High Input
P1193. Inlet Air Temp. Circuit High.
If you have all of those at once, it is not likely that 3 different sensors go bad at the same time. Check harness and connections to ECM,

Well the starting problem could be fuel related, code 134 is for an open circuit going to the O2 sensor in front of the catalytic converter.
I doubt the code would cause the engine not to start.

My 2005 crycler town and county power seat is not retracking?

Try replacing the throttle position sensor. They can get 'noisy' electrically which confuses the computer, yet doesn't set a code for the defect. This sensor is supposed to deliver a smooth transition from near zero DC volts to near +5 volts as the throttle position is increased. Hope this helps!

replace them with a brake light bulb to check if the bulb is really good.

That doesnt sound like a fun job that line goes from the front to the back do you believe it to be clogged

It's called the low side and should have a black top on it. Should be very visable..