I have finally bitten the bullet and bought a heated front and rear screen in Bullmotif's sale.
I would like some advice on wiring them up.
I intend to fit an additional fuse box and found this article very helpful
1.
Can anyone tell me the the current rating of the cable I should use and what colours of cable I should use for the different bits? I'd like to keep it as sympathetic to the other wiring.
When both are on you had better NOT also have the headlights on! So yes - the 40 amp relays will be fine, and use heavy(ish) wire - the same thickness as feed the headlights. You can go your own way with wire colours - but ignition controlled stuff tends to be green wire with tracer colours added - and the relays for these should certainly be wired through the ignition circuit, although the actual power feed wires should NOT be through ignition or they would overload the switch. These wires could be brown perhaps with tracers after the relays , since brown is the main 12v +ve bus on the car. Black wire is the norm for the -ve earth connections.
They don't come with any instructions or anything other than the screens. I phoned them and they said that there were so many different ways of wiring them up and types of switches that they don't supply any electrical parts with them.
