12v help required

ebo

Nov 9, 2009
94
99
Essex
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A class Carado i449
Exp
Since 2009
Does anybody know where I might locate the 12v cable and relay that powers the fridge when the engine is running on a 2007 Lunar Roadstar 800, which is based on a Fiat x250 3lt. The fridge doesn't work on 12v, the fold out step doesn't retract when ignition is on and the 12v electrics still work with the engine running, reading the instructions for the sargent EC200 PSU2007 the electrics shouldn't work and a message should be displayed on the control unit stating that the engine is running, this is not happening so I'm thinking that these may all be connected. There is a wire coming from the 12v connection on the fridge that would appear to also run to the step, but the 12v wiring to the fridge appears to come from the PSU I've looked under the bonnet for a relay but can't see anything obvious, any advice or views would be appreciated.
 

pappajohn

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Aug 26, 2007
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the 12v relay is generally near the engine battery along with the split charge relay.

The relays are usually common 30amp automotive relays.

It does sound like the fridge relay has failed.

relay.jpg
 
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Badknee

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Aug 25, 2014
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Full timing for five years and loving it!
Jaws put a rant up about this unit today, you could check that out.
 
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lunarman

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Sep 23, 2008
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Given that the step is not retracting and the fridge is not working it would seem that the system is not detecting the output from the alternator d+ I think it is called. Lunar seemed to put the relays in a variety of places. In 780 I had it was in the engine bay. In the 786 it was under the floor in the wardrobe

Not much help best of luck
 
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OP
ebo

ebo

Nov 9, 2009
94
99
Essex
MH
A class Carado i449
Exp
Since 2009
Update to the original post, my van is fitted with a Sargent EC200 interface unit that amongst other things controls the fridge, step and disables the 12v electrics when the engine is running, so appears this could be at fault, have spoken to Sargent who do a fixed price repair service so will be sending it to them when I get the chance and will report back
 
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