Series 3 Diesel Cold Start

Hi all, just got my Landy back from the garage for the MOT and asked for a glow plug switch to be plumbed in. I was surprised to see when I got home that the plugs are being powered straight from the battery to a switch and then straight to the plugs, bypassing the coil on the bulkhead. Is this right? Whats the purpose of the coil?

Cheers

I think it depends what type of plugs you have. The original 'pig tail' type were about 1.8volts each, were wired in series and needed the resister to reduce the power. The later type plugs needed the 12volts, were wired in parallel for reliability.

Perfect! Considering there are new plugs in it and its wired in parallel then it makes the resistor redundant although how can I have the cold start bulb lighting?

Wire it in parallel too so its a warning light?