# Ducato Wiring Diagram and electrical problem



## garadi (Jan 8, 2007)

Hi

Can anyone help with obtaining a set of wirinhg diagrams for a Fiat Ducato 1999 2.8 TDi ?

I have the Russek Pocket Mecahnic but that doesn't cover my problem.

Better still can anyone help with solving the problem of 3 volts at the IN TANK FUEL PUMP whilst I have 12v at the fuel cut off switch.

Any members replying wil get points and you know what points mean.

Regards



Graham


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## rayc (Jun 3, 2008)

garadi said:


> Hi
> 
> Can anyone help with obtaining a set of wirinhg diagrams for a Fiat Ducato 1999 2.8 TDi ?
> 
> ...


Have you got 12v on both sides of the fuel cut off switch?


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## garadi (Jan 8, 2007)

Rayc

Good question ,answer is No earth one side live the other. Now understanding that the inertia switch when closed ( i.e. in normal position)sends power to the impact relay which in turn sends power to the glow plugs and the injection pump and iy does look as if it has any relationship with the in tank LP fuel pump,whic is currently recieving only 7 volts irespective of whether the \inertia switch is open or closed.

All this seems to indicate that the In Tank Fuel pump is not connected to the inertia switch and I have been chasing the proverbial red herring !!

Still leaves me with the problem of why is the supply to the ITF Pimp only at 7v.

Any light you can throw on the quandry will mean valuable EXTRA POINTS

Thanks 

Graham


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## rayc (Jun 3, 2008)

garadi said:


> Rayc
> 
> Good question ,answer is No earth one side live the other. Now understanding that the inertia switch when closed ( i.e. in normal position)sends power to the impact relay......
> 
> Graham


If the inertia switch is a straight forward switch then when in its normal position the voltage should be the same on both sides.
My understanding is that the switch feeds negative to the relay to operate it and your readings suggest the switch is open. [ the 12v you are reading is the 12v for the relay which goes through its coil to the switch. When the inertia switch is operated i.e normal position, then you will get negative on both sides.


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## spatz1 (May 19, 2011)

Electrics were never fiats strong point , and my car is likely to develop this fault as others do when it wont start and no fuel is being delivered....
Its likely if you trace the coloured wire back to a push in type multi plug along the circuit (yellow in my car) you ll find the pin inside the conecter has had high resistance and will have burnt slightly and this limits the voltage getting through... clean up and make the conection good and you re off again...


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## raynipper (Aug 4, 2008)

garadi said:


> Hi
> 
> Can anyone help with obtaining a set of wirinhg diagrams for a Fiat Ducato 1999 2.8 TDi ?
> 
> ...


Hi Graham.
My 2000 Fiat Hobby 2.8 started to give intermittent problems with the horn and fuel gauge. 
It all transpired to be a rusty earth to the chassis below the L/H headlamp.

Ray.


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