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After replacing the sensor with the same type, I don’t see telemetry data on the transmitter display.

If the sensor is replaced and the transmitter no longer displays telemetry data, so this isn’t a sensor or transmitter issue. This is due to the transmitter’s “memory” and the specific serial number of each DUPLEX sensor.
JETI Duplex: Discontinued BEC, sensors & telemetry

Here you can find relevant information, user manuals and support regarding these products:
Expander E4, MRPM, MRPM-AC, MT 125, MT 300, MU-3, MULi6s, MUI, MVario, MGPS, MSPEED, MAX BEC 2D.
Firmware Update: Receivers, controllers, sensors, Tx Modules

This article describes the procedure of how to update the electronic devices manufactured by JETI model. Prior performing the update, you should obtain a USB Adapter or JETIBOX profi that is able to function as a USB adapter as well.
MSpeed and other telemetric sensors of Duplex system
The speed of a flying model is a figure that is interesting for us, though we frequently only estimate it, but we measure it with difficulties. Thanks to MSpeed sensor it is possible to not only measure the speed precisely, but also monitor maximal and mainly minimal speed of the model.
MUI sensor used as a fuel gauge
The article describes what to do to replace the fuel gauge by means of current and voltage sensors. Useful for pilots of jet models.