Fixed, replaced both CR29, CR 30 PAD diodes, only one was bad, but replaced both from the same lot #. They are in parallel with each other , so they share current. Did the calibration on the capacitor section and is good to go. I am noticing that measuring in the pico farad range that reading do wander a little bit, compared to my DE-5000, but it has kevin leads on it.
But a question, On top of the unit there is a sticker that mentions, that there will be poor readings in the low capacitance range unless the unit is grounded. Any ideas on why that would be the case, ( maybe something to do with the switch mode power supply in the unit not being shielded?). I noticed that it appears the chassis/case is only grounded through the external power supply ground.