Sun Oct 14th 2007 14:46:21: Denon UD-M5 repairs

Just gave my Denon UD-M5 hifi thingy a service, and here are some tips for repairing various problems:

Symptom: Press power button andy system dies

Turns out this a problem with the 5V power rail. If you take the top off the system, the PSU board is on top and easily accesible. Check continuity through the transformer. There is one coil that should not have continuity, but the rest should. Then check the fuses - there is 1 obvious 20mm fuse in a fuse holder and 3 more that look like resistors. The problem with my system was that one of the resistor like fuses to the 6V regulator had gone. I replaced it with an anti surge fuse (RS 226-0686), and also replaced the other fuses at the same time. Sorted!

Symptom: Volume control does not work properly

This is a problem with the rotatary encoder. Replace it and you are sorted. RS sell a suitable one (RS 265-1739), however you'll need to attack it with some side cutters to extend the flat and chop off the end so that the knob fits.

Symptom: CD struggles to read discs

If this is the case, then you are a bit stuffed. To improve the situation you can try increasing the laser current, however this will kill the laser in the long run. To do this take the power supply PCB out (or at least get it out of the way) and then look through the hole towards the back of the CD mechanism. With the aid of a bright light, you should spot a blue (in my case) potentiometer. Rotate this a few degrees clockwise (easier said then done - I ended up using a long pointy thing) and test. Repeat until it plays more reliably. But don't blame me if your laser dies!


I'm sure you're going to get done for aiding and abetting acts of terrorism one day :-)

Comment by Andy Allan at 15:19 on Mon 15 October 2007

My Denon ud-m5 is unstable when playing CD's.

It jumps tracks and bits on the same track and carries on like a angry person..

Can I service/clean the laser or something..can you help please

Thanks Fred

Comment by Fred Janssen at 23:44 on Sun 6 April 2008

Hi Fred,

Sounds like you need to turn the laser current up a bit as per "Symptom: CD struggles to read discs".


Comment by Gary at 22:05 on Thu 22 May 2008

I have just been given a faulty UD-M5. Only occaisonally recognises a CD after a lot of whirring and clicking and skips horribly if it does manage to play a track. I have just found that it will play perfectly if the right side is tilted up on a small apple about 5cm high! So the laser power must be OK. Something must be ever so slightly misaligned. Is there any way of making adjustments?


Comment by Aidrian at 20:47 on Wed 22 October 2008

hi my denon ud-m5 will not play anything. i turn it on and it says protect and i havnt got a remote control for it so i can not get it off. how do i get it to normal so i can play cds and mp3 again?????

please please please help me!

Comment by michaela at 18:55 on Sat 14 March 2009


Our UD-M5 showed all these symptoms. Symptom 2 we've lived with for years, next came the disk read problem, finally it gave up completely (point 1). Thanks to Fogma, whoever you are, I've fixed it and it's back blasting us out.

Thanks very much for your advice!

Comment by Lee at 17:46 on Thu 14 January 2010

Ive just bought a ud-m5 but have not got the users manual thus I cannot set the time,and also would like to know what it will do.any idea where I might be able to get a copy.

Thanks Les

Comment by les at 16:39 on Sat 6 February 2010

I was about to chuck out my UD-M5 due to it failing to read discs. So it would not even move through the tracks of a lens cleaner. However, noting the comment about lifting the right side up, it worked! - I then ran a lens cleaning disc through and it is currently back to working on the level!

Comment by Geoff at 23:15 on Fri 31 August 2012

ive also rescued a UD-M5, cant open the cd trays and disk 1 light is lit orange and wont do owt!!!

any ideas pls guys thanks

Comment by banksy at 7:46 on Sat 22 June 2013

Add New Comment

(Never displayed publically)
HTML Tags allowed - <b>bold</b>, <i>italic</i> and <a href="http://...">Links</a>
Type "NoSpam" in Here:


<< Back