I've repaired several of these with the low battery warning, and I've never
seen this prevent startup; more likely there are some marginal caps in the
standby power circuit, or a marginal zener in the standby regulator circuit;
these will cause highly intermittant operation, including long periods of
normal operation; sometimes simply unplugging and replugging the power cord
will recharge the circuit enough to get it going. Eventually the standby
circuit will need servicing, if you can find a tech willing to work on it.