Mechanic pulled up a P1811 code. The car drives smooth. Transmission doesn't slip or stick. What does it mean?
Hi, thanks for writing in. This code occurs when the PCM sees that the transmission takes longer to shift than the given parameters. The PCM uses several parameters, like load and speed, to tell the transmission when it should shift. When a vehicle is overloaded, pulling a trailer, or towing a trailer in overdrive, it can cause the code to set. It would be recommended to clear the code and see if it sets again. If it does, it may be a sign of more serious problems within the transmission, or transmission control systems.