I hope it helps
If your heater is on all the time in the rear this is what to do.
The rear heater box is found under your Delica behind the drivers door.
I have two electric motors that operate the flap.
Water and mud has entered and damaged the motors.
This caused the heater to stay on.
By releasing the lever on the motor box you can close the flaps.
Now the air can go through the roof airconditioning vents instead of the floor vents.
Family is now happy.
This the rear heater box located behind the drivers door
Remove the four small screws holding the cover on.
Dirt and mud in the cover
With the cover removed you can see the control motors.Remove the screws.
Disconnect the power and move the retaining clip to disconnect the lever
You can now remove the motors.This means the flap to the heater can now be closed by pulling it forward.Airconditioning vents can now work.
This is inside the motor box and you can see the damage.With the motor seized the lever can't move and in our case the heater was on all the time.
Relace the heater cover and your ready to go untill you have the replacement parts