Fuel Filter housing connector burnt out and car not starting

[chabadav]

our 2.0TDCi 2007 Galaxy has had problems to start on cold mornings for a while and yesterday it again started then stopped and would not start again.
When I looked under the hood I noticed there was no fuel in the clear line from filter to high pressure pump on top right of engine.
Then I noticed that the wires going into the plug on top of the fuel filter housing cap were exposed. After removing the plug it was clear there was a major problem as completely burnt through - see pictures. There was obviously a short circuit and overheating.
I presume this is the problem and I have ordered a replacement housing top with attached plug and will solder on the wires but does anyone know what this is? Is there some sort of flow meter in the top of the housing or another type of sensor. Why would this cause the fuel line to be empty?
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[johnnyroper]

To burn up like that I would say it is something that draws a bit of load so probably fuel filter heating element.

[chabadav]

Thanks - yes, that would make sense, however I do not understand why this would cause loss of fuel in tubing to pump. I will also check more carefully for leaks caused by damaged lines or line joints.

[johnnyroper]

If itââ,¬â,,¢s damaged the housing it could let air in to the system. Best to get it replaced and see how it behaves after.

[chabadav]

I have just installed the replacement fuel filter housing + connector, after cutting wires and splicing together.

I had to wait for the item arriving from the UK - could not get one here on eBay with attached plug, hence the delay.

I cleaned and filled the bottom part with fresh diesel, bleed by vacuum suction from return pipe and the car started after a couple of attempts and all perfect!

There are absolutely no air bubbles in the fuel lines now, definitely must have been a damaged housing causing the leak!
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