Forget it. I have the exact same problem. I'm sure it's a $10 worth of parts fix but Sunfire wants $450 for a " complete overhaul " plus $50 to ship it. I emailed Sunfire "Customer Serve Us" and asked to talk to a tech so I could find out how to override that damn auto on circuit. No deal. Schematic for just the auto on? No way. When I explained how ill used I felt by them I was accused of being cheap! Take your car in for an oil change and get charged for a transmission rebuild? If your sunfire needs a new amp and driver then it's a smokin deal. If it needs a resistor, diode and capacitor then you're not very well served. I think Sunfire outsources for the service on these things! They probably couldn't keep up as these subs are not very dependable. Mine failed the first month I had it. Shipping it is a pain. No local service available. Bottom line is I will never buy another Sunfire product. A shame cause when it works it's pretty impressive. Thinking about a Velodyne 10" MiniVee.
It's unfortunate Sunfire has so little regard for their customers.
Here is their response.:
While we can certainly understand your desire to save money we are under no obligation to provide schematics for our products to anyone. Nor is any manufacturer. We consider the repair price to be appropriate for the knowledge required and the work performed in diagnosing, replacing defective components, testing as well as the shipping costs back.
Matthew S. xxxxxxx
Customer Service Supervisor
Sent: Thursday, November 13, 2008 5:28 PM
To: Brian xxxxxx
Subject: Re: True Subwoofer MK IV auto on and Standby malfunction
I cannot see how I would be well served by spending $50 to ship and $450 to repair a subwoofer that has such a trivial problem. I have read on various forums that Sunfire products are unreliable but I had no idea that their customer service department practiced what amounts to extortion! So my choice is spend $500 to fix a $10 problem or throw the junker into the garbage. How convenient that there are no local authorized service centers for your products! Does the phrase Customer Service mean anything to you people?
I'm sure it would take no more than 5 minutes for a Tech to email me a procedure for overriding the auto on circuit. I am a Instrumentation Technician and fully understand that I would assume all risk of rendering the unit inoperable. It is of little use to me as is so I have nothing to lose anyway. I am willing to sign a waiver relieving Sunfire of any liability.
From: Brian xxxxx
Sent: Thursday, November 13, 2008 2:11:36 PM
Subject: RE: True Subwoofer MK IV auto on and Standby malfunction
Gary, I am sorry to inform you I can not send out schematics or Part information. The only thing I would be able to offer would be an RMA to ship the unit in for repair.
Brian D. xxxxxxx
Posted At: Thursday, November 13, 2008 3:14 PM
Posted To: Sunfire Support Email
Conversation: True Subwoofer MK IV auto on and Standby malfunction
Subject: True Subwoofer MK IV auto on and Standby malfunction
My MK IV now requires an uncomfortably high volume setting in order to trigger on. Then when I adjust the volume to a normal level the sub returns to standby in only a few minutes unless the source content is bass heavy in the extreme. Is there a trim pot setting on the circuit board that adjusts the bias for the auto on function? Can the timeout period be manipulated ( RC ) and increased to 1hr? If you could email me a schematic for just the auto on and timer circuit I would greatly appreciate it. I'm sure for the cost of less than $10 in parts that I could fix this problem with a little assistance from 1 of your Service Techs.
I would prefer to disable the Auto-On and Standby feature entirely and just power on the sub manually with a powerstrip. Is there a jumper I could install to keep it powered on indefinitely?
Your assistance is appreciated