It’s always possible somebody somewhere has posted a wiring diagram on a forum in response to a request, but generally I would think the odds of finding one are pretty low. The best thing to search in Google for (if you haven’t already tried) would be the words, wiring diagram, or wiring schematic, followed by the model number of your appliance ( Where to find the proper model number and serial number on a washing machine ). There are some repair manuals being sold but these are very general and not model specific and written by third parties. All the ones I’ve seen are very much out of date although they may well still contain some useful general advice and knowledge.
The only sure way to tell if a element is faulty, even if all the above faults are present, is to use whats called a ohmmeter, a ohmmeter is a device used for testing all types of electrical values, including resistance between 2 conductive device. To test if a element is working or not a engineer would connect a ohmmeters live and neutral wires to the corresponding connectors on the element and check for a positive reading, no reading would mean a faulty element, the engineer would also use the ohmmeter to read across both terminals again and the earth terminal on the element but in this case a positive reading would mean a faulty element and a negative reading would mean no fault on the earth to live and earth to neutral connectors