Feel the back cover half way down to make sure the element is heating. If it is, is the drum turning? If not it is most likely that the belt has snapped (or slipped). Take off two screws at the top back holding on the top cover. This will allow you to edge it up sufficiently at the back to reach your hand in and check the belt.
TURN OFF & REMOVE THE ELECTRIC PLUG BEFORE ANY ATTEMPTS AT OPENING!
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