Thanks Jim and Mark. Seems to me that you learn something everyday. I have never heard of an end-stage coil and I presume this is the transistor which Jim was talking about. Anyway, I have got the garage looking for this earth point first and to help them it would be better to know whether this is on n/s or o/s. It does not have A/C.

I have studied the LT current waveform in the Pico Library and I now wonder if I should see the same wave-form bearing in mind the type of coil I am testing. If it is, and the current is incorrect, I would then wonder why this would be. Electricity to me unfortunately is and remains a mystery apart from the very basics.

Regards

Pete M