I have similar problem with my Acura MDX 2004 model. When the transmission gear is engaged to either D5 or D4, it will only change 1-3 and will not transmit further. On applying further acceleration, the engine RPM will go high and vehicle speed will not increase and the D5 green light will start blinking. However, when engaged in D3 the vehicle will be moving without issues. The vehicle has been taken to a mechanic shop but it is yet to be corrected. I suspect transmission switch problem. Any advice offered will be appreciated.

Chuks