This started to happen a year or two ago on Ignition OFF, since when I have been carrying spares, used two until ...
This week I had to turn out to rescue Mrs.B and show her how to swap 'em, but then a 2nd blew on Ign OFF at home! We are losing heart
Electrical history:
- We bought it "converted" from importer: all he did dc was add acc.socket for sink pump(+fitted ac hookup/sockets), no leisure battery
But I have had to get the Alternator replaced twice: - original 3 years ago (perhaps due to water ingress when rad blew "V6 Head Gasket, Coolant loss, Idling", "V6 SAGA.. blown radiator..")
- another last year (perhaps due to oil drips, given oil filler directly above , but 6 months after "V6 will not crank after flat battery")
- maybe main fuse blowing (not any sub-fuse) points to a cumulative effect ie no single faulty circuit? Eg is 100A now under-rated for (I hope) a mid-life vehicle, whose motors now draw more current than when new? Last year I measured 40-50A at battery leads (engine running with dead alternator). So it seemed quite plausible that, when about to turn OFF after a journey, fan running could add another 20-30A, whereupon closing say window/door ~20A could nudge it over the ton. I've bought 120A fuse to try, any Resettables out there?
- but (1) sounds less likely than my 3rd Alternator on Ignition OFF spiking and blowing main fuse. Is this one failing too? On schematic "A-2 Starter & Alternator", there are paths via only "100A MAIN" (otherwise unfused) from both Alternator "2A" (RHS) and Starter Motor "A2-01" (LHS, but no probs at Ign ON!) Is there a diode pack that needs replacing? Or could some sort of inline TransZorb be retrofitted?
Help appreciated ...