check the cord
turn off breaker, then pull dryer out and unplug cord. Look at the prongs to see if surrounding rubber is dark and melted. Then remove cover on dryer over cord connection. Check that all nuts or bolts securing wires to dryer are tight. Then remove cover plate from plug and remove plug from wall. Now tighten all screws securing wire to plug and re-install all mentioned. Also as mentioned check to see wires are firmly tightned to breaker lugs, then Remove the breaker from panel. This can be done with wires still hooked to it. Look at the buss in panel where breaker touches to see that there is no burning or corrosion. Once you have completed this, you probably have located the problem. If any part of this seems out of your skill range, hire an electrician (these practices do have dangers) Good luck....
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