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All of the components were in good visual condition - not charred or discoloured.
The inductors should have resistance in the milliOhms range and measured a short i.e good.
The capaciotrs all measured as open loop, i.e. were not short.
The diodes measured as open loop in one polarity and gave a forward voltage in the other.
Despite the caveats about in-circuit measurement, both diodes had a forward voltage of~190mV, which is about right for a Schottky diode.
As far as can be ascertained, noe of the external components have failed, though it was not possible to determine that the capacitor and inductor values were correct relative to the typical application circuit.
Bear in mind that this was done using otoo large multimeter probes, 3.0 diopter reading glasses and a powerful head torch.
Nevertheless, that would appear to confirm that the TPS 65185 chip is the culprit for my broken e-reader.
Now I have to set about finding a replacement chip, replacing it and seeing if that fixes it. I am aware that I may need to set VCOM (the flat flax cable is marked -1.83, presumably volts) but I will cross that bridge if I ever reach it.
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