Dometic refregerator 2652, the inside refer. light and the check light on the front blink when i open the refrigerator door. then stops a bout 20 sec. after closing the door

On most Dometics, When you have a cooling problem follow these steps and it will resolve your problem or at least tell you what is wrong.
Check main terminal Block for proper Voltage
Check Heating element for proper ohms, 2652 is 44ohms
Disconnect P-2 wire on board for approximately 12 to 18 hrs. This makes the unit run constantly in case there is a clog in the unit.
The only other thing you may do is check the thermistor operation, Unplug the P-2, remove the thermistor from inside the refrigerator, put it in ice, You want the thermistor to drop to about 32 degrees, Check the ohms, they should be at 8,000 to 10,000 ohms.
If all checks out, you have either a bad board, not common, or a bad cooling unit, common

Check the 5 amp buss fuse behind the frig.

Model 2652 Refrigerator The fridge has been perfct till this last trip. the auto light is on and its not getting cold no red lights and i have pluged in as well as unpluged propain is full but i see some yellow dust inside the big cyinder.we may have left the frezzer door open for a couple hour.

I found that they rewired the 12 volt supply, red wire, thru a heat safety switch on the burner unit and it was open instead of being closed and cut off the main 12 volt supply to the control board. I connected a jumper wire around the new switch and the frig works . either the new switch is bad or too close to the heating unit.