We have a 1998 Sterling Europa. Two electric plugs (1 black and 1 grey) connect to towing vehicle, a 2005 Peugeot 407SW. When we use our fridge on gas or 240 volts everything works ok. On our last trip when we tow and switch the green fridge light off and the red switch on, with the engine running, the red light comes on for 15 - 20 seconds, then goes off for 3 or 4 seconds and then comes on again for 16 seconds and then off again for 3 seconds. It continues in this on/offf routine until we reconnect to gas or 240 v. Can anyone advise of this is a terminal situation for the fridge?