Not sure but I've done something wrong wiring the relays.

Did you splice into the hrw feed to operate the relays ?.

Yeah, the blue/yellow in the white plug under the external fusebox.

Strange if you've you've got a drain to earth from there, are your relays still operating for the front screen.

The Blue and Yellow is ignition controlled, so it shouldn't be live with the ignition off, and the front screen is on a timed cycle like the hrw.

Just a random thought, you're not using latching relays ?.

http://www.extremeautoaccessories.co...1304710880.jpg

That's not latching is it.

It doesn't look like it, to be sure it would need 12v and an earth applied to terminal 85 & 86, if it clicks when you apply power, and then clicks again when you remove power it's a normal relay, if it doesn't click when you remove power then it's a latching relay.

The coil symbol between 85 & 86 is for a normal relay, so non latching.

85 - connected to blue/yellow - 12v when engine running and HRW is on, 0v at other times.
86 - connected to earth - 12v when engine running and HRW is on, 0v at other times.
87 - connected to constant live - 12v at all times.
30 - connected to front screen - 12v when relay on, 0v when relay off.

That all makes sense - what doesn't is no resistance between the switched live 85 and earth regardless of it being connected to the relay or not.

How can it cause battery drain when plugged to the relay?

That's very odd, the readings for the relays are fine, I can't really see how it can be draining the battery.

I would have said that the heated screen draining the battery was a Red Herring, but for the fact that it doesn't do it when the feed for the relays are disconnected.

Where have you taken the 12v feed for terminal 87 from.

The same terminal in the engine bay fusebox as you did.