Took me three weeks to sort out my misbehaving fridge. This is a 3762 model made in 2011. The later model 3762's don't have a thermocouple on the gas burner which is the traditional design. It looks like the ignitor electrode and the thermocouple are combined into a single device with a single wire. This requires a controller card to deal with this new device and Dinosaur Electronics doesn't make controllers for this hardware setup yet which is a bummer.
My first symptom was the temperature on the front panel reading 40 degrees too low and the unit never calling for the heater to fire. After reading airforums all night I tested out the thermistor and it was reading a correct at 8.5K ohms in ice water so the usual culprit wasn't my problem.
That's when I noticed the unit was never wired correctly. The 12V
heater wire (blue) and the interior light wire (red) were reversed (see photo and wiring diagram). Also the cable guard cover wasn't closed because the cable to the top readout display didn't have enough slack to make it around the bottom of the controller card. The wires in the harness were obviously pinched during assembly but tested out for connectivity okay. Not knowing if the reversed wires were an issue or not, I took the controller card out looked for bad solder joints, blown fuses or if anything was burnt out. These newer cards have surface mounted devices and are coated with epoxy so board level repairs is going to be a nightmare. Normally I'd get out a soldering iron and reflux the board to fix bad solder joints, but didn't do that due to the epoxy.
After reassembly the temperature readout dropped even further giving me an intermittent E2 error code. After more testing of the 120V heater element, solenoid, electrode, fuses, thermal fuses, etc, then I started getting E3 error codes.
Replacing the controller card fixed the E2 and low temperature sensing making me believe there is a bad solder joint in the original card somewhere. The E3 code ended up being a pin in the electrical molex connector that backed off (see photo). The red wire is the culprit and goes to the thermalfuse which when open trips the E3 code. I had to rotate the pin 180 degrees and re-insert into the molex so that the cam could snap into the holder correctly.
Obviously disappointed in the Dometic build quality...
Hopefully this will help other 'streamers with diagnosing newer fridges. I'd look very closely at the cabling!