19 years ago my van broke down with a total electrical failure - nothing worked at all. Got home by hot-wiring from the battery positive to the coil positive. On investigating, it seemed that VW takes the vehicle's 12 volt supply (apart from the starter) from the post on the starter. This had rusted and fallen off. This seems to be a weak point in the design Yesterday the same thing happened. Rather than again go under the van to fix the poor connection, today I took a completely new lead from the battery positive straight to the (now severed) arterial supply under the fuse box. Then disconnected the supply in the engine compartment. Seems to work perfectly, although I'll be fitting a circuit breaker at the battery end shortly. This seems an altogether better solution than having join(s) in the wiring open to the elements.
Yes the eye terminal on the starter solonoid is prone to the elements. Better to extend it straight to the battery. It is a direct connection to the main starter lead at the starter so is not fused from the factory. Personally I would put a fuse in it. Make sure the connection you make to the original feed wire is a good weather resistant connection or you will experience the same problem. Place the fuse near the battery away from the elements. You can get a maxi blade fuse holder & fuse. Add up your max current draw to get the right fuse rating. And buy a spare just in case.
I asked some time back why there is no fuse between the battery and the ignition, whereas all the other circuits for lights, horn ,wipers etc are fused. It seems that VW, in common with other car makers decided that it’s safer to keep the circuit unfused so that the engine doesn’t cut out unexpectedly. I guess the whole loom might melt but there’s less danger of this than breaking down in traffic if a fuse blew. I’d intended to fit a fuse into the ignition circuit until I learned this.
'Tis true. Uncommon to have a fuse in the ignition circuit. But...I've never liked that gert length of unfused cable running to the front. Could stick a 60A fuse in it.
In my setup, I have two huge engine batteries with the positive terminals hardwired together, and a "off / 1/2/Both" master switch on the earth side. The "second" battery is in the rear cupboard (VERY well secured!) and it's from this battery that the new lead is attached. I've ordered a 50A breaker as below
