blowing something but fuses look ok,what could it be

TERRY, April 2009

The relay under the bonnet is probably for the fridge which has its own power from the car battery.The leisure battery will have a 25 or 35amp fuse which should be fitted very close to the leisure battery itself,if all is ok check fuses on the power unit,there will be 3 or 4 usally,if there ok and you are getting no power when switching on the 12v then fault usally lies at the switch itself.even if you are getting 12v to and from the switch it can still be faulty,because of the amps drain.clean contacts on the switch,but you should take out the fuse for the car and leisure battery if removing the panel for safety reasons.you can also check for 12v at the rear of the unit if you have a wiring diagram,if its a zig unit usally number 2 is the car battery and number 4 is the leisure battery.all odd numbers are earths,

mikec, May 2009

Thank you Bob i will look? It is a swift sundance motorhome with a fait cab 2003.It has relays and fuses i thought it might be a relay 12v 50a i found next to fuses under bonnet,going to see if i can get one to day fingers X.

TERRY, April 2009

Unfortunately a process of elimination.
Check by substitution the main [colour coded ] spade type fuses of the 12volt circuit. Follow both wires to ensure there isn't break or an in-line cartrige type fuse as used in older cars. If you find one push the two sections of the holder together and twist the larger one to release the glass cartridge fuse inside.[10amp I think]. Check both the battery leads are clean at both ends. Check the control panel 12volt on/off switch is not causing the fault.
Good luck

Bob, April 2009