towing electrics

[manwithbins]

Has anyone on here fittied their own towbar and electrics? The towbar is no problem,but in the electric kit purchased it says to connect to the input side of the module which controls the bulb failure check system,but I have no idea where this is or even if this is necessary.
Does the DIS measure current flow to react to bulb failure or by some other means?

Thanks.