If the washing machine is not producing any hot water, but the cold water is coming into and filling the washer, then you may have a faulty water inlet valve.
WARNING! Before attempting to work on any appliance, make sure that all power (electricity) and utilities (water and gas) have been turned off and/or disconnected on the appliance. Read this before you start any repair.
The water inlet valve opens and closes, allowing hot or cold water into the washer. Since there are two solenoids, one for hot and one for cold, one of the solenoids can fail, while the other can continue working.
Another issue with the water inlet valve is the screens inside the water inlet valve can become clogged with sediment and minerals from hard water. Turn off the water supply and disconnect the fill hoses to check the openings of the water inlet vale. You may need to remove the part in order to clean the screens to see if this fixes the issue.
If this does not fix the issue then test the hot water coil using a multimeter to test for continuity. If there is no continuity, replace the water inlet valve.