Can your car overheating cause your transmission to act up?

Yes those things can be related and not necessarily a transmission problem. Many electronic controlled transmissions (started in the mid 90's) have what is called a 'limp mode'. That is when the computer that controls the transmission senses problems it tries to protect you and itself by boosting the system pressure to reduce slipping (and heat) and locking into 2nd gear. They pick 2nd because it should allow you to drive somewhat normally in normal city conditions without shifting gears. 3rd gear you would have trouble getting moving from a stop and first you would only be able to go around 20mph. In your case the issue the transmission is seeing may be the elevated temps. Like others said the transmission fluid is also cooled by the radiator with the engine coolant. If the engine coolant temp is high the transmission will also be high. The transmission may think the temps are high because its slipping so its trying to protect itself and allow you to safely drive to a shop to get it fixed. Once it cools it cant find a problem so it goes back to normal till it gets hot again. I would try to address the high coolant temps first and see if that solves the transmission problem. 230 is the upper range of normal so if there is noting wrong with the cooling system or engine it may be that the transmission is slipping / getting hot on its own and that is what is raising your coolant temp.

Yes, overheating may affect the car's automatic transmission. Coolant lines from the transmission run to the radiator and back, usually to a tank on top or side of the radiator. Their purpose is to keep the ATF (automatic transmission fluid) at operating temperature. If the coolant level drops or the engine overheats, it certainly may affect shifting and performance of the transmission. Good luck with it.

nope a bad working transmission has nothing to do with motor cooling system and 230 is pass hot its boiling you need more than trans work