Upon power-up, the cylinder does not spin on my Panasonic AG-MD830E
S-VHS VCR. Although it loads (actually half-loads) the cassette
properly, any transport command fails following the full-load because
the cylinder is not spinning. The display reads error E-4, which means
"malfunction in cylinder section." Without a service manual, I don't
know where to start to debug the problem. Any help will be much
appreciated...thanks!