I am not sure about your 385HV but on my 383, which I believe is similar, I have to be in Manual flash mode and adjust my flash via the power settings. Under most circumstances I use 1/4 or 1/8 depending on the situation.
The Sunpak 383 won't fire in auto sensor mode in bright sunlight either?!?!?!?!
What's the deal with all these flash units not being usable for fill flash in bright light?