Click to expand.Fluke are excellent instruments. They may supply the schematics for a fee. I am not sure. Normally you should give the meter to them for service. They service them mostly at the modular level. They can also calibrate the meter for you, which you would not normally be able to do yourself. We send out our Fluke instruments once each year for calibration, service, and certification.
In consideration of the usefulness and the high cost of a new Fluke meter they are worth to send out for factory service. Fluke is not very expensive for their service charges.