Help needed repair Pioneer DJM-900NXS strange high peaks - AVS Forum | Home Theater Discussions And Reviews
Forum Jump: 
Thread Tools
post #1 of 1 Old 11-08-2019, 03:09 AM - Thread Starter
Join Date: Nov 2015
Posts: 7
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Liked: 0
Help needed repair Pioneer DJM-900NXS strange high peaks

Hi mates, thank you for your kind help.

The mixer has this problem, after boot it shows repetitive high peaks for about 2 minutes (on speakers sounds like a short "tic tic", it's about about twice a second, but not regular. After about 2 min they start drastically reducing and the led go normally to zero, the sound od fource may then be visible on leds. Curiosity: After 2 minutes, only if I activate the mic1 I can still hear some tic tic, but they also reduces too.. till disappear. The mixer then is working regulary. Chances are if I switch off and on soon it keeps work perfect, but if I wait some time it will do the same problem. The problem is then connected or to the temperature of one component or to the lack of capacity of one/more condensers.
The mixer was working every day about 17 hours, but in really ideal conditions, I can suppose the problem is connected to lifetime of some components. For example I noticed the C1201 was a bit "fatter" and I substituted it, as well as C1213 & C1206, C1412, and from that time the situation seems a bit improved, before the problem didn't disappear, now yes after 2 minutes.
I can't replace all condensers, also it's dangerous to do because it's not easy to remove them and the pcb may be damaged.

If I have to guess, that "tick" looks a reset of all the ADC, maybe the CPU is expecting something from them and still resetting until receive a proper answer.
There were others strange behaviours: in test mode it showed "software version 0", then accessing the update mode (but without updating it) it showed correctly 1.32, then again in test mode was correctly shown 1.32. I tried also to upload again firmware. When the software version was 0 in test mode I couldn't make test of fader and other sliders, the led were always off, now is ok. Probably when the problem was present in test mode I couldn't test all the trim potentiometers, so the problem is probably on the analog board, maybe I've to remade the joints of the flat cable?
Here is the video I made:

Thank you a lot for help
BarabbaFurLAN is offline  
Sponsored Links
Reply CD Players & Dedicated Music Transports

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off