Bit long-winded but hopefully answer "some" questions that may be thrown back at me. Have a Dometic RM4401 3-way fridge with an auto-ignitor on start-up. Have used before with no problems whatsoever. Cooled fridge on 240V prior to leaving home and fridge temp monitor showed 4 degrees. Travelled to destination on 12V, monitor showing 6 degrees (very hot day). Switched off 12V, opened gas line at bottle and lit stove to check gas flow. Followed step-by-step instructions to start fridge on gas, auto-ignitor flashed 6 times and went out (indicating gas working?), held gas button for further 10-12 seconds. Heat seemed to be coming from top outside vent. Half an hour later, fridge temp had risen to 9 degrees and didn't seem to be working. Shut all down, left for fifteen minutes and tried again. NOW the ignitor would not flash (start) at all. Changed to definite full gas bottle, re-checked gas line taps, checked van fuses but auto-ignitor refused to flash ??? Tried changing fuses, bleeding more gas through using stove, swearing, prayer............but all to no avail. Did not want to attempt to remove outside vents at that time in case of damaging them so far from home. On inspection I did notice some spider webs around bottom vent. Attempted starting over next 3 days at different times but it was not to be........lucky a friend was nearby who generously freed up space in his fridge........which has a manual ignitor Before I venture to the local dealer (who is very good) to see if the problem is terminal is there anything else I can do to trouble shoot the above issue ? I'm not aware of any other in-line fuse(s), etc that may need checking but will have a go at removing vents now that I am home and it cools down tonight ? Any assistance / guidance would be very much appreciated !!!
Have you tried a gas lighter gun and using that when it is auto starting? I use that in the manual system when it wants to be tricky but needs two people, one to hold in the gas knob inside on the fridge and one to click the gas lighter.
Happy lighting.
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Got to keep moving and as Hippocrates the modern medicine guru once said "Let food be thy medicine and medicine be thy food
Things that you can check are the gas jet, and the burner also check that the vent is clean if all black soot is there the burner needs to be cleaned. You will need to get to the back of the fridge to do this work. Hope this helps.
Many thanks Hammer & allinone for taking the time to reply to my post. Hooked up the 240V and got the fridge down to 4 degrees (empty). Switched over to gas (lit stove, checked flow, etc, etc) and b*gger me if the ignitor doesn't give 6 flashes and go out. Kept the finger on the gas button for 20 seconds and then left it for 2 hours. Now at 2.7 degrees on #5 setting on the fridge with warmth coming from the top outside vent (ambient temp is currently 14 degrees). Maybe it's a faulty part of the ignition system that has an intermitent problem (or maybe I'm the problem ??? ) Will leave overnight and see what happens tomorrow. Possibly the bouncing around on the road coming home may have helped but I am totally confused........but sort of happy it's working again . Cheers and thanks again
Half an hour later, fridge temp had risen to 9 degrees and didn't seem to be working. 
Shut all down, left for fifteen minutes and tried again. NOW the ignitor would not flash (start) at all. Changed to definite full gas bottle, re-checked gas line taps, checked van fuses but auto-ignitor refused to flash ??? Tried changing fuses, bleeding more gas through using stove, swearing, prayer............but all to no avail. 
Did not want to attempt to remove outside vents at that time in case of damaging them so far from home. 
On inspection I did notice some spider webs around bottom vent. Attempted starting over next 3 days at different times but it was not to be........lucky a friend was nearby who generously freed up space in his fridge........which has a manual ignitor 
Before I venture to the local dealer (who is very good) to see if the problem is terminal is there anything else I can do to trouble shoot the above issue ? I'm not aware of any other in-line fuse(s), etc that may need checking but will have a go at removing vents now that I am home and it cools down tonight ? Any assistance / guidance would be very much appreciated !!!
. Cheers and thanks again 
