polo was of the road for 6 mths getting repainted , at the time it as being driven back in august 2012 the centrel locking only worked from the pas/door , the car has been sitting since then . so last week decided to get it up and running again , but now the centrel locking will not work at all , i checked the pump in the boot and it was really wet so i replaced it with a working used one , but still the locking wont work any ideas what i could check next folks .

You could start by checking the fuse (Fuse 21 from memory)

With the ignition switched 'on', use a test lamp or voltmeter to check for something like battery voltage at the terminal of the red/white wire that enters the pump.

NOTE: use a separate earth to the one on the pump, as if its own earth proves to be faulty, you will be looking in the wrong place for the fault!

If the above proves to be OK, run a temporary earth wire from the brown AND brown/black terminal to a known good earth, if it has an earth fault, you should be able to operate the locks with the temporary earth in place.

If, withe the ignition switched 'on', you connect a temporary positive (+ve) feed to the pump terminal with the grey/black wire going to it, the pump should run. If you now change this temporary feed to the terminal with the grey/red wire going to it, the pump should again run, but this time in the REVERSE direction. ( The pump produces pressure in one direction and vacuum in the other)

IF the above seem OK, the problem COULD be with the door switches, but before you take off the door cards to check, it is simpler to first check for any broken wires inside the converluted connection between the doors and the door pillars. Also unscrew the multi-plug on each door and check that the pins/sockets are free from corrosion.

Moisture is number one enemy of these pumps, so the original one has probably seen better days (check for any signs of burning on the PCB)

When you have got it sorted, make sure that the pump compartment is water tight. Someone on here recommended putting the pump at a higher level, which makes good sense.

Regards.

If they had the doors off for the repaint, I'd check the disconnect plugs on the A post including the plastic pipe for the vacumm locking

If they had the doors off for the repaint, I'd check the disconnect plugs on the A post including the plastic pipe for the vacumm locking

thanks thats great advise ill give it a go .