Just got this 1990 212S machine with 1500 hours on it and the Transmission Pressure Sensor Light is constantly on. Fluid looks red like ATF and is full. Have not ran it since the light is on, but it goes in and out of gear just fine with no slippage or hesitation. If I raise to front of the machine with the bucket about 18" to 24" , or if I back up quickly and apply the brakes so the machine stops abruptly, the light will go out and sometimes stay out for a while. Any suggestions as any help is appreciated? Thank you for your time.
One thing comes to mind, on my 210S (1994) the light for trans pressure was always on. There was a small leak around the sensor unit located on the drivers side near the rear of tranny, ( 2 wires to the sensor ) I replaced the sensor and it solved the small leak and light went out and stayed off. But it does sound like your low on fluid from what you stated when the light goes off sometimes.