which wires to tap ???
 

just fitted boost guage and now i need to tap into a lights wire so it switches on at the same time

anyone know which colour this is under the dash

also i assume we are on brown for earth, black for neg and red for bat+

anyone???

If the boost gauge is for the house thats fine, but not for the car!!! :eek:

Sorry don't have the wire colours to hand.
Thick black wire is generally the Earth and I think the lighting from the rear fog switch is purple (but pop the switch out and check it with a volt meter)

Lighting supply can be taken from any switch that lights when the side lights/head lights are turned on or from the cigarette lighter. Make sure you get the right wire (not the ignition live!!)

If you are unsure get a pro to do it. Shouldn't take them more that a few minutes :)