Technical Parasitic battery

[joelew2010]

Hello,

I have a drain on my battery. It is draining from full in a couple of days without use. The cause of the drain seems to be coming from the cable connected via the brown 70A midi fuse on the battery itself. Any ideas what this is for and what might be draining my battery.

Thanks

 

[Communicator]

Please supply the vehicle details, then someone may be able to help.


If you have a handbook for the vehicle, it should give details of the midi fuses.

 

[joelew2010]

Sorry its a Ducato 150 multijet 2012 2.3

 

[Communicator]

Hi,

I do not have detailed info for the x250, but one of the midi fuses supplies the engine bay fusebox, and another supplies the cab fusebox & BCM.

 

[Anthony489]

Hi joelew

I have attached a circuit for the X250 main power feeds, it's spread over two pages. The 70 amp fuse near the battery terminal is F72. It supplies power via Relay T13 to four other fuses in the dashboard fuse panel:
F33 for the rear 12 volt socket
F45 for the Power windows controller in the driver's door, the door mirrors and the Instrument Lighting System

F47 for the Driver's window

F48 for the Passenger's window

Relay T13 is only supposed to have its coil energised (i.e. its contacts closed) when the ignition is switched on. You could pull out Relay T13 and see if the current drain stops.


Please bear in mind that electrics are an area where Fiat couldn't resist tinkering over the years, so your vehicle may be slightly different !

Stop press, just spotted another connection so will investigate !

 

[Anthony489]

Just to update, Page 4 of the circuit reveals that the Red (R) cable from F72 also feeds:


Relay T30 / Fuse F58 Sidelights

Relay T31 / Fuse F57 Under seat heater
Fuse F59 Self Levelling Suspension
Relay T66 / Fuse F55 and F56 Heated Seats and Rear Passenger Current Outlet
F63 and F65 Passenger Additional Heater

Apart from the sidelights, the other items are options not often fitted to UK vehicles so you may find that the relays and fuses are not fitted.

Just wondering if your vehicle has been modified, and someone has used one of these spare Fuse/Relay positions to "pick up" power for an accessory ?