Hi everyone,

My family are presently stranded in rural France in our Fiat Ducato 2001 motorhome.

The electrical connection from the fuel filter water sensor has come away entirely from the unit. Due to this, the van won't start.
There are three wires that were connected to the unit and lead back into the vans internal electrics. The three wires are Red, Blue, Black.
Does anyone know if I can join two of these wires to complete the circuit and get the van going again?

Hi Matt

I only have information on the later Ducato, 2006 onwards. However, the water in fuel sensor may well be very similar.

The three wires are 12V DC power, Ground and Output Signal to the ECU.

The colours are PROBABLY Red for 12V, Black for Ground and Blue for Output Signal. I cannot guarantee this, and it would be wise to check with a cheap multimeter if you can get hold of one. At the very least try a spare bulb between each wire and an earth (e.g. engine metal). The one that makes the bulb glow is the 12V.

The sensor Output signal will switch between something close to 12V and something close to 0V (ground), depending on whether or not there is water in the fuel. Unfortunately I don't know which way round it is.

Assuming my guess of wire colours is correct, I suggest you try shorting the blue wire to the red wire to simulate a high sensor output. If that doesn't work, short the blue wire to the black wire instead to simulate a low sensor output. For safety, I suggest you short them via a spare fuse of the lowest rating you have.

With luck, one of these choices will fool the ECU into "thinking" that there is no water in the fuel.

Im wondering if this is the thing stopping it running though..

My 2007 jtd car:1248cc

Had the fuel lamp on when I bought it.. ran fine

The sensor in the filter assembly was combined fuel quality AND fuel temperature.

Was there any particular issue before you investigated the damaged wiring ?

varesecrazy said:

Im wondering if this is the thing stopping it running though..

My 2007 jtd car:1248cc

Had the fuel lamp on when I bought it.. ran fine

The sensor in the filter assembly was combined fuel quality AND fuel temperature.

Was there any particular issue before you investigated the damaged wiring ?

Click to expand...

I am begining to think the same.
I have been actively researching eLearn, with the assumption that the vehicle has the metal canister type of filter, and not the plastic housed UFI filter, as fitted to later models.

My information only relates to x244 models, but with the metal canister type of filter, the sensor only seems to operate a warning light.

With the later "green"??? or UFI filter there is an input to the ECU, which could prevent the engine running.

Many thanks for your responses

The fuel filter has a metal housing. It is a Mann Filter WK 842/8.

The problem began with a warning light telling me that I had water in my fuel filter.
After the light coming on the vehicle started and drove a few miles without any problem.
Later in the day, I unscrewed the plastic cap mounted under the filter in an attempt to drain the water.
The worn out electrical cable came away from the plastic cap and the unit lost it's electrical connection with the vehicle.
From that point the vehicle wouldn't start.

Ok..
Its older tech.

My old 1929's had a sensor at the lowest point

The french..Purflux..and similar I used to buy in the Hypermarche just had a big white plastic drain spout.. the sensor was then uncoupled and redundant..(in a bag in the shed) no warnings..and no issues

These were older than yours though..
pre. JTD


Ok.

A little lateral thinking

For a running JTD you require

Air and Fuel

Does the padlock: key symbol work as expected

( do you hear the tank in the fuel pump whirring??)

These might be your issue.. maybe from a short as the plug crumbled..

Charlie

When I put the key in the ignition and try to start the engine, there are no lights illuminated, but there is certainly a loud churning / whirring from the engine.

I tried the wiring suggestion: blue to red and then blue to black, but the vehicle wouldn't start with either configuration.

If I have shorted the fuel pump, is there a fuse I can replace?

Many thanks again for all your help

Matt Godfrey said:

I tried the wiring suggestion: blue to red and then blue to black, but the vehicle wouldn't start with either configuration.

If I have shorted the fuel pump, is there a fuse I can replace?

Many thanks again for all your help

Click to expand...

Despite much diagram gazing on Fiat eLearn, I am unable to trace the supply for the water in fuel sensor. For non "green" filter versions, the filter is shown on the instrument panel wiring diagram, but the diagram suggests that the supply is obtained via wiring shown on the engine managenent drawing, where I cannot see it. However using connector wiring tables it seems to be obtained from the engine bay fusebox. This is consistent with wiring diagrams for "green" filter equipped vehicles, where the supply is taken from F11, designated secondary services. The electric fuel pump is supplied from fuse F21 in the engine bay fusebox.

Wiring in a 2001 vehicle could be different.

You should be able to hear the electic fuel pump whiring when the key is turned to the run position, before trying to start the engine.

That's so very helpful and very much appreciated.

I haven't owned the vehicle for very long and I can't locate the engine bay fuse box.

Does any one know where it is located on out left hand drive model Fiat Ducato 2001 coach built Hymer motorhome please?

My apologies for not being able to help (no experience on this issue) but a relevant query which might assist those can with a diagnosis:

When attempting to start does the engine turn over?

Matt Godfrey said:

That's so very helpful and very much appreciated.

I haven't owned the vehicle for very long and I can't locate the engine bay fuse box.

Does any one know where it is located on out left hand drive model Fiat Ducato 2001 coach built Hymer motorhome please?

Click to expand...

When you initiall switch on the ignition

You should see a 'self.test'

Several lights on

Then the..
curly glow plug light
Key-padlock immobiliser light..

should both go out after @5 seconds


Leaving only oil and battery symbols..

What else is showing at this point ?
Handbrake..

When I put the key in and turn for ignition no lights show at all, not even for the initial five seconds and no lights are showing after the five seconds either.

The engine does turn over.

I have located the 10A fuse (in the glove compartment) for the fuel filter water sensor and this is blown, but I'm guessing this wouldn't immobilise the engine.

If fuses in glove box are torpedo shaped, then wiring does differ from later models.

Does blown fuse supply more than faulty sensor??? Seems possible.

Perhaps you can separate sensor connector, or insulate live wire with any sort of adhesive tape, including medical plaster.

Replace fuse, and any other blown fuses.

Check for battery & oil lights at least, before trying starter.

Continued use of starter will quickly discharge battery.

Also wise to conserve habitation batteries.

Check around the battery in the engine bay for the large maxi fuses check one of these hasn't blown

The fuses in the glove compartment fuse box are typical Macro spade type fuses.

The blown 10A fuse in glove compartment fuse box supplies the following:
Fiat Code
Electrical Heater Control Lighting
Headlight Beam Adjustment Lighting
Chronotachograph Lighting
Clock Lighting
Direction Indicators
Reversing Lights
Water In Fuel Sensor
Direction Indicator Warning Light
Water In Fuel Filter Warning Light

Found two Macro fuses in engine bay near battery, they were both intact.

Trying our best to preserve habitation battery; spent the last 2 evenings reading by candle light.

The blown fuse would stop the engine starting if it supplies the fiat code system as that's the imboliser if that's dosnt give the ok the start won't inject any fuel

Rode bike to nearest auto supplies shop.
Bought replacement 10A fuses.
Replaced the fuse and the van started first time.

I was then seen dancing around the van making squawking noises like a large bird in joyous celebration.
Thank you all so very much, ignorant types like me need good people like you to get them through sometimes.
I can't thank you all enough.
My family are all smiling.

Wishing you all a wonderful day,
Matt

Hi Matt, Have you checked your earth? Clip jump lead from neg battery terminal to engine. try to start. If this works, bad earth. clean all earth strap connections on both sides of engine and bodywork. I have an old van and the symptoms you describe are similar to a bad earth. I snapped my water sensor wire 10 years ago with no ill effects. I now drain the fuel filter twice a year just in case. Never found any water. Best of Luck, Ian