Hi Im an electronics tech who put 3 kids through Uni by fixing electronic like this.   A friend got this one, it was found in a back yard in the long grass. After a clean up to rid it of slugs and earwigs it looked quite good. This model had no 240V power supply. it was only 12V/24V. It came to me after it had been plugged in and didn't work. The fuse in the power lead was gone. Testing over the power leads it had a short. I traced this back to the board on the compressor. Removing that I found the Electrics inside were OK. There was a big diode which looked like a possibility and yes dead short;. This is a BZW50-33B a transition diode. Coming clean I had to Google that up. Turns out to be a protector across the supply. Its not easy getting in to that depth, so I chopped it out. Now that is not such a good thing, but I found a place on the other board and fitted a new one there. Reading on this site, these have a few faults one being the thermostat. I tested that  ( thanks to a guy on this site) and it tested Ok. But I am going to add a modification. Who wants a light in a chest fridge. Half the time it will be covered anyway. So I disconnected the lamp plug and that can be plugged into the thermostat socket if needed. I will wire a thermostat in the place where the bulb was. Sure the purists will say it will not read correctly, but this thing is going across the Simpson on a sidecar. A couple of degrees out who cares and 2 thermostats delivered for $5 from Ebay, she'se Apples.   

     The power cord didn't inspire me, a fag lighter plug  bouncing up and down on a sidecar? eh no. Some wire from Supercheap and I hardwired the thing. built a screw in type fuse holder and I also put in crowbar diode across the input. (Connect + to - and the fuse blows).

     Now thanks to someone on this site you have a diagram of a power supply. this seems to cause issues. I read one guy was going to buy the FET and IC and this is partially the reason for my post. Think that post was 2010 and I think that's when that unit got tossed.   SMPS was the thing I repaired most and there are a few rules you ignore at your peril.  Take the supply out. DO NOT TOUCH OR TEST ANYTHING. With it out, if you have a resistor  or some form of load (240V lamp etc) short out the main filter capacitor with your dummy load. This is a must. The reason is simple if the start up resistor is gone that capacitor is sitting at about 340V, that is painful. Also start testing the FET and chances are you will kill it.

   What gives me that warm and fuzzy feelingl looking at this diagram, three things (1)  R2 100K 2W kickstart resistor. Made a few bucks changing kickstart resistors.  (2) C4 100uF35V filter resistor for IC1. If that goes high ESR  (Equiv series resistance) then the control of the supply is erratic and Im unsure as to what IC 1 does in that instance. Someone wrote their PSU was reading high but reduced after a few minutes, its C4.   If you change it get the best you can IE low ESR 105 deg.  and (3) that relay. Relays on DC just don't do it for me. They weld contacts ETC.  

    Well that's me. Hope the Waeko lasts the Simpson because I want a loan of it for the Nullarbor next spring.   Rob.

That guy is still here.

Ah Thanks for the info, it helped me a lot.  No I have to edit this. Most people would recognize the skill involved in nutting out that diagram, I do. My hat is off to you sir.  Rob