audi a6 c5 2.5tdi AKE no start

erxxd

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Hello, car is audi a6 c5 2.5tdi AKE 2000 year automatic (front wheel drive)
Last time the car started with -17 degrees celsisus weather, started right up, ran for like 5 seconds then stalled and wont start anymore.
So Far i have checked the high pressure pump belt, tank fuel pump fuse, the clear fuel line from filter to high pressure pump (no bubbles) all that seems fine.
I opened the tank lid from the trunk, fuel pump runs fine when i gave it direct +12v, however the pump wires did not get any signal when i turned the ignition on. Is that normal, does it only get power for few seconds after ignition switched on or does it only get power when cranking the engine?
Engine turns over just fine but does not start. I have done my research and to my understanding is that the pump only swirls around the fuel or is suppose to fill some "bucket" in the tank, from which the high pressure pump should suck the fuel itself. I opened the fuel supply line from the filter and nothing comes out with ignition on or even when cranking. I have vcds lite program that only showed some engine mount fault and thats it. I dont have access to a proper diagnostic software at the moment. Regarding the fuel pump, could it may be a relay problem?
I know that these engines are known for their high pressure pump failure but i just want to make sure i have checked all the other possibilites before going to assume the pump has failed.

Also a few weeks back my key fob stopped unlocking/locking the doors from the remote (operates from the door lock manually only). Im sure its just a battery because when i turn ignition on the car and key symbol goes out so i assume its not a immobiliser problem? not sure if these symptoms apply to immobiliser problems.

Any kind of help is more then appreciated, i actually was planning to sell the car in a few months so i wanna make sure i dont change or do anything, thats not the problem. Trying not to miss any possiblites for this kind of fault before going to the high press pump.

thanks to all the answers and help in advance, sincerely appreciate it.
 
I'd apply voltage to the tank pump & see if the car runs fine then at least you've proved it's fine otherwise, then check the relay circuit as usually there is one for the lift pump.
 
Hi erxxd, this same thing happened to my AKE. What had happened was the fuel control unit located on top of the high pressure pump had a burn out transistor in it. This is the unit that has the multi pin connector attached to it. to remove it you have to cut the 4 thin wires that actually link it to the pump.Be sure to mark them to avoid confusion when re-connecting. If you go on line and look for Bosch VP44 pump repairs there are a couple of companies who will test and repair the control unit for around £50. Mine came back almost by return post and the car started.Hope this helps.