Trevor, Darren, my picture previously shows why the physical damage I had on the board led to my suspicion that this capacitor was at least
one of the causes of this difficult to diagnose and resolve fault.
Having replaced the capacitor [I'm sure it is electrolytic Trevor, I have retained the old one and will dig out specs for you when I can find it] and not cured the problem my next port of call must be replacing or fixing the acid damaged tracks on the board.
However as Roger's board shows no damage in his picture I could be barking up the wrong tree.
Unfortunately I don't have the wiring schematic for this unit, or don't even know if this is shown in the WSM. [I strongly suspect it may show inputs and outputs and connectors, without showing a circuit diagram for the control boards]
However, one question comes to mind in relation to Trevor's and Darren's line of reasoning; assuming or accepting the cause is related to sensor issues, then how do you explain it if the control unit that is faulty is replaced with a known working unit, and then proceeds to work OK? Most if not all people who have fixed the problem in the SVX have had this experience. Does this not imply the fault is within the control unit?
I do accept that the cabin temperature sensor is actually installed inside the unit [there is a tube feeding the unit air from the slotted holes in the dashboard] and in replacing the control unit you are actually replacing at least one sensor as well.
Also with the SVX control unit it needs to be taken into account that when the box loses its marbles invariably the
outside temperature display goes ga-ga and starts blipping, beeping and blinking. A new and working control unit will obviously not replace the outside sensor, but yet will appear to operate normally. I've not so far heard of anyone replacing a control unit
and the outside sensor. So is this symptom of failure relevant?
Assuming for the moment that possibly my boiling capacitor is a one-off situation and not the normal cause of the problem, can anyone suggest how we might go about testing the temperature sensor?
Joe
[Oh, and Roger, the + and - things you mentioned earlier are not switches. I think you are referring to the bulb holders for the lights for the panels
]