Dometic RV portable cooler fault codes
12V compressor coolers/fridges (e.g. Dometic CFX) show alerts and warning numbers for low voltage and compressor/sensor faults.
How to read the code
Read the alert/warning number on the display. Low-voltage cut-out is the most common — check the 12V supply and cable before suspecting the compressor.
Models covered: every code below applies to the Dometic CFX3 75DZ, CFX3 95DZ.
All documented codes
E31 (low voltage alert) warning
The cooler stopped running on 12/24V DC because the incoming supply voltage dropped below … Warning 01 / 02 (NTC sensor) warning
The cooler's temperature sensor (an NTC thermistor) reads as an open circuit (01) or a sho… Warning 03 / 43 (communication) warning
An internal communication fault between the cooler's electronic components (for example di… Warning 11 / 12 (NTC sensor) warning
Same kind of temperature-sensor fault as Warning 01/02, but for the small zone of a dual-z… Warning 32 (fan overcurrent) warning
The cooling fan is drawing more current than allowed, which the controller treats as a fan… Warning 33 (compressor start) warning
The cooler's controller tried to start the compressor but it did not start, so the control… Warning 34 (compressor speed) warning
The compressor is running but cannot reach or hold its target speed, so the controller rep… Warning 35 (overtemperature) warning
The temperature of the cooler's electronic controller has risen too high, so it stops the …
The cooler stopped running on 12/24V DC because the incoming supply voltage dropped below … Warning 01 / 02 (NTC sensor) warning
The cooler's temperature sensor (an NTC thermistor) reads as an open circuit (01) or a sho… Warning 03 / 43 (communication) warning
An internal communication fault between the cooler's electronic components (for example di… Warning 11 / 12 (NTC sensor) warning
Same kind of temperature-sensor fault as Warning 01/02, but for the small zone of a dual-z… Warning 32 (fan overcurrent) warning
The cooling fan is drawing more current than allowed, which the controller treats as a fan… Warning 33 (compressor start) warning
The cooler's controller tried to start the compressor but it did not start, so the control… Warning 34 (compressor speed) warning
The compressor is running but cannot reach or hold its target speed, so the controller rep… Warning 35 (overtemperature) warning
The temperature of the cooler's electronic controller has risen too high, so it stops the …
Which of these codes apply to your model?
Not every code below exists on every Dometic portable cooler. Pick your model number to see only the table that applies to it — and which codes it will never show.