Thanks for comments.
What I need to be sure is that infact the tuner is at fault.
I have tv schematic but it doesn't show enough details about what
voltages should be on each pin of the tuner.
Can anyone help with another check I could do to be sure the output
voltages of the tuner are infact at fault?
Is it possible for the higher voltage at the AGC pin to be caused by
somethingelse?

wrote:
In sci.electronics.repair Jerry G. wrote:
This can be a defective RF stage in the tuner, or an AGC fault. The
tuner, when defective is changed as a module. You would be best off to
order the service manual and follow it through, or give out the set for
proper service. Take care for serious safety issues when working in TV
sets.

This particular model tuner by the way, was made by Temic.

---
Met vriendelijke groet,

Maarten Bakker.