One thing i don't understand is electrics, its all a black art. We have a split charge relay system for our vehicle battery and leisure battery. We have the ignition and radio connected to the vehicle battery and the fridge a 12 volt power socket in the rear and a 12 volt power/lighter in the front. The problem is the leisure battery only seems to work when the engine is running i.e. the electrical equipment only works with engine running. I have checked the voltage with a multi meter when the batteries are disconnected and i am getting above 12.5 volt on both. Then with the engine off, i turn the fridge on the voltage doesn't go down but the fridge doesn't work i.e. it doesn't drain the battery i thought it may not be holding its charge. Then i turn the engine on and the fridge works immediately. I have even disconnected the vehicle battery while the engine is running to see if there is a fault there but just the same symptoms. any clue of what it may be or whats happening, like i said at the start i just don't understand electrickery
Our fridge has a switch which comes on provided the engine is running. If the engine wasn't running the leisure battery would drain very quickly as fridges take a lot of juice so you have to manually turn it on if you want to. We don't use the fridge unless we switch it to gas or have hook up.
If you have a fridge like on my Westy you will find that it is powered not from the leisure battery but from the alternator and main battery via a relay. The relay is built into the fridge control panel. Is it possible that your power sockets are wired into the fridge circuit and so not coming on until the engine is running? Your fridge has to run this way as the battery won't last very long otherwise.
WHS^^^^ Or possibly there's a PO relay only switching the leisure battery in with the ignition. Fridges are only supposed to work on 12v when running so if you've pulled the power from that circuit, that's hat you're getting.
I'd guess that too. You may have a leisure battery in the van but you need to follow the wires and work out what is actually attached to it. Remember BMW drivers have indicators in their car, they just aren't used.
If its a 3 or 2 way fridge it should have a relay somewhere so that it is only feed from the leisure battery when the engine is running. This is because they can pull 10amp so will flatten the battery within a few hours they are only meant to be run on 12v when traveling If you want a fridge that runs on 12v you need a compressor one. Have a look at this how to on fridges http://thelatebay.com/index.php?threads/fridge-types.11369/ .
You would only want the fridge working on 12 v with the van running. Mine was through a relay that only energised when the engine ran. I have much the same now I put a split charge unit in. Your 12 v sockets should work though when stationary. Is your wiring system inherited from the previous owner? If so it may be worth tracing how it all works and getting it working how you want it. If you don't have the confidence to do it yourself it may be worth paying an auto electrician to have a look for you. It will be well worth getting things as you want, lights where you want, sockets and I pod chargers etc...
I don't know if this is normal with an alternator but it certainly used to work on my old Ford Pop which had a dynamo.
I was always under the impression that if you pull the power from an engine, it dies. alternator or not. If crumpets kept running then it suggests that the engine would be running from the leisure, which in turn suggests that something is wired wrong and both batteries are running in parallel not two separate systems.
Alternator to common 12V+ on starter and hence to everywhere else. The battery is connected in parallel.
Yes I had thought it was something like that. On older vehicles like the 6V Beetle once the dynamo is spinning it provides enough electricity to run the engine. It does need a bit of battery power to energise the coils at start up but then keeps going unaided.
As said you need a battery connected for it to run In this case the leisure battery i A split charge system is just a switch that joins the battery's positive together when there is voltage coming from the alternator You should also not have the leisure battery disconnected when the engine is running as the split charger will be switched so the battery lead that was on the leisure battery is now live and floating around in the engine bay.
Thank goodness for that as i disconnected both batteries and it still ran, after reading Zeds quote saying it will bugger up the diodes in the alternator i may now have a secondary problem and need to start on new thread "buggered alternator any help" Just one for the question of the fridge, a small school boy error, it is an after market 12v fridge and not a westfalia, waeco fridge will this make a difference
If you had the fridge connected then you might not have done any damage - the alternator regulator will have backed off the field control, provided something draws current the voltage stays under control.
