VI

Fault diagnosis

Answer a few questions to narrow down the cause. The steps follow the order technicians actually use: rule things out from the outside in, from cheap to expensive.

← Start over

Has the device never worked, or did it work and then fail?

Never worked from the start Was working fine, then dropped out
Before opening the machine. Disconnect power, wait for capacitors to discharge, and photograph the current wiring. If the machine is under warranty, call us first — opening it yourself may void the warranty.