Jump to content


Member Since 10 Mar 2014
Offline Last Active Apr 11 2014 03:45 PM

Topics I've Started

Crown XTI4000 no power problem

11 March 2014 - 12:36 AM

Hello. I am new to this thread and decided to join in hope someone can help me out trying to figure out a problem I am having with my Crown XTI4000.
I have two of these and one stopped working over 6 months ago. I am a photo technician myself and have decent electornic skills and decided to give it a try and started troubleshooting the amp. I spent countless hours checking all major components of the amp to find faulty components. I ended up replacing two IGBT's and FAN7380MX IC. Even though they were bad, replacing them didn’t change anything. There is still no power.
I think I have looked up all the information/threads about problems with XTI amplifiers on line , especially those with no power and followed guidelines in those threads. Still no luck.
I am getting around 160VDC between TP28 and TP31 and 16V on D31 after removing R375. With R375 installed , voltage on D31 keeps oscillating. Same thing with +15_CTRL/ TP28 - keeps oscillating as well. Nothing seems overheating with power applied though I try to turn it off as soon as possible every time after testing.
I have tested so many different components ( transistors, diodes, film capacitors, electrolytic caps, resistors ) and found nothing out of ordinary. I have fixed many soldering joints as well. I keep thinking something is either open or one of the smaller and/or hidden smd components I haven’t checked is shorted out. I even removed heat sinks to check some components that were hard to reach. I am out of ideas at the moment, though I am not giving up on the amplifier yet.
I would appreciate any input from someone who might have had similar problems or knows XTI amps inside out.