pre heater diesel
 

I have a 2003 CDTi with pre heater with fob. It has gradually ceased to work. I think the problem is that the diesel fuel is not reaching the unit. What is the likely reason ? Where is the pump for the feed please ? When switched on it will 'hum' for a short time and then stop. No fuel is coming through the small narrow feed pipe. Help, basically. thank you.
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The pump is just in front of the driver's side rear wheel mounted on a bracket.. It is not a continuous 12v feed so you need to swiped 12v across it to check it is working.

Him John.
Photo of the said pump on the car below, as above flick some power across the pump to see if it is working or not, most of the time though these pumps are reliable.

pre heater pump
 

Many thanks. I am sure that will solve it for me. Will have a go at it tomorrow.

working on it now pump works on separate battery but no click / no life when ignition s/w on,or fob used,is there are fuse or relay somewhere?

If its working it must be clicking, you need to tap 12v to it about every half second to test it, The FBH after an initial test of the pump doesn't call for fuel until after 30 seconds so it is not necessarily a fuel pump issue you have, describe what happens when you turn it on

i agree as i found out to my cost .it may not be the pump. any number of issues can cause it not to work.ie is the fan coming on?is the water pump working?you can hear the fan.and the water pump you can feel vibration from it etc.when mine packed up i assumed the fuel pump was had it.replaced it not cheap btw.then discovered later the fan and the water pump had gone.in other words there was nought wrong with the pump.

The original post mentioned an ongoing deterioration. Could that be the continued accumulation of soot build up?

Cheers,
Glenn

If you are sending a startup command via telestart, without the engine running, and all you hear is humming, then the primary cause could be the air fan. If the air fan fails to start, the FBH will do nothing at all and appear dead.
You are correct about the fuel not reaching the unit, that is because.....
The FBH dose pump will only be initiated after each primary component has past an electronic test, then, basically.

The air fan purges the combustion chamber.
The water pump is started.
The glow plug is lit.
The dose pump primes the combustion cap at idle rate.

The air fan starts to ramp up to full load, the dose pump steps up to full load speed, the glow plug is extinguished which takes on the role of flame sensor.
If the FBH senses fuel ignition, it continues to ramp up to full load. If the flame sensor does not detect fuel ignition, the dose pump is stopped, the FBH goes into shut down, and the air fan purges the combustion chamber.

Your problem could more than likely be your PCB.
you have a PM