Can an AC overcharge stop the compressor from initially turning on after the vehicle has sat overnight, or does the pressure have to build up before the ecu will shut it off?

I know it is common for an AC undercharge [low pressure] to stop the initial compressor start up, because a low pressure would be there even if the vehicle has sat overnight.

 

it would have to be way overcharged to trip the pressure switch at start-up. i think the minimum cut off is 28psi and the max is 450psi! i don't think you could even push enough in to be that high at system equilibrium (off; not running).

what model year accord is it?

you could have a faulty pressure switch or something completely different causing it to not work.

 

your receiver dryer may be shot (full of moisture) and it cant hold no more. you may have water in your system and the compressor cant compress water. too many cans of refrigerant is not good. most people do this and have issues later. have an AC shop diagnos it. you may need a receiver drier, leak test, evacuation, and refill of refrigerant

 

good call on the dryer. i agree.

 

95, Ex

It's the Thermostat Switch Sensor on the Evaporator. I narrowed it down to either that or high pressure. I never heard of high pressure doing it immediately but it seemed possible. The T-stat doesn't kick on the fans or the comp when I jump it. Everything else checked out.