Water pump still runs ( ignition off ) + flat battery

[innocenti]

Hi thought I'd post a query on here .got up to a flat battery on my 1.9 td ( golf ) t25 this morning .
Lifted engine lid to remove the battery and the little water pumP above oil filter etc was still running ( causing battery to flatten not use the camper for about 3 days so don't know how long it's been like that .
I pulled the supply plug and it stopped obviously . I'm told now its a sensor fault ?
Can some one tell me where or post a pic pointing out all sensors I can pull the supply from to see if that cures it one at a time ?
Or point me in the direction if this advice is a bum steer ?
Cheers in advance Steve

[innocenti]

bump ^^^^^^
cheers steve