Fluke 45, optocoupler replacement

[vidi]

Hi folks,

I'm trying to repair Fluke 45 for a friend and one of the issues is that optocoupler U3 is half dead (stops optocoupling at temperature 30 C). I wonder if anyone here did a replacement and if - what component has been used instead, since I'm not able to find any specs. What I know about the old one: it is phototransistor optocoupler with forward threshold voltage 1.06V.

Thanks.

BTW, it seems to be the cause of ERROR 8 (Analog Measurement Processor A1U1 dead) and ERROR 9 (Measurement self-check failed).

[coromonadalix]

If i search IL11  optocoupler,   as i see it on an teardown photos : https://www.flickr.com/photos/eevblog/with/21129692555/

Google gives :  Siemens  IL9 IL10 IL11 series

http://pdf.icpdf.com/PdfOld/icpdf_datasheet_1/IL9_datasheet_19792/325327/IL9_datasheet.pdf


Seems to be a perfect fit ...