Hi i have 2 1991 golf gtd's both with a similar problem

1st one, The glow plug control unit was broken and had been bypassed with a switch, i fitted a need glow plug control unit and now the glow plugs come on when the ignition is switched on but they dont turn off and cause the battery to run flat.

2nd one, there is no power getting to the glow plugs when the ignition is turned on, i have swapped over the control unit and tried a known good relay also swapped the temperature sensor on the coolant flange next to the coolant temperature sensor with no sucess there is power getting to the control unit but not coming out of it.

Can anyone help?

Thanks

Gareth