Will not start!

Went to start it this morning. Ignition on, lights on dash came on as normal. Waited for the glow plug light to go out. Turned the key. CLUNK. All power goes off. Nothing.
Got out and slammed the door and noticed that the power came back so tried again. All normal untill u turn to start.

Kind of sounds like a loud relay click.

I'm stummped. Wonder why slamming the door brought back power.

200tdi by the way.

Tiz either Starter Motor or Starter Motor Solenoid. The "Click" is the relay switching.

time to get the starter motor off and have a good clean and check.

or tap the starter with something. Teh carbon brushes get stuck, and they're supposed to be pushed down by springs so that as they wear, they're still in contact. Just giving it a tap is enough to get them back in place, hence slamming the door fixing it. albeit temporarily no doubt

slamming the door didnt make it start, just made power return,(interior light came back on)
As soon as i tried to start it again all electrics failed again.

My dad's mate a similar problem with his Renault van, it turned out there was a dead short inside the battery. Try changing batteries and try again.

starter might be jammed in the flywheel, put in gear and rock back and forward, this may sort it.

first off check your battery, starter motor and earth connections. If they are all ok the next step would be to get your battery charged and tested. If possible try another battery on it. If it does the same again then I would put my money on it being a dead short inside the starter motor.