Hi , jumping in on this
exactly similar occurred today . It rained a little bit, been really dry . Disco 2 2001 v8 . Tape over the sunroof for years .
I leave it unlocked . Went to use it ( had last done so 20 hours previously) . Cluster lights on , doors locked , only worked manually . Front right indicator light and repeater on . Radio and climate on . It started even if I “immobilised “ it . I disconnect battery to have that hope it would fix everything and boost power and improve mileage at the same time , naturally it won’t start at all now as the immobiliser now works , and the remote doesn’t .
I will try the heater out of interest , but the explanation about the Pcb improving momentarily seems plausible ( given the heat in the car could be significant) .
or should I just get another BCU?
I have just got a series 3 so no doubt I will be back , I have no clue about this really . I like ‘em though .