Alfred B for Model Number JVM1540SM4SS Fan goes on but will not heat or defrost am waiting did you get.
Answer Alfred, You will want to check the magnetron on the unit for resistance of less than 1 ohm. If the resistance is open or more than 1 ohms then you will need to replace the magnetron. Read More... Answered by AppliancePartsPros.com | Friday, March 18, 2016