My Innovate MTX-L shows "22.1", "CAL", "Htr" all the time, or freezes. What does it mean?

"22.1" constantly usually means the sensor reads free air/very lean, or it is not connected or calibrated; "Htr"/"CAL" constantly means the sensor heater cycle or calibration never completes. First check power and ground, the sensor cable pins, and try a known-good LSU 4.9 sensor. If the gauge still freezes, shows the same code with a good sensor, or doesn't power up, it is faulty; send it to us for testing and warranty replacement.