Orion MBR not charging

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My Orion MBR is no longer charging the secondary battery:mad:. When it's powered, only the red light turno on (indicating it's ON) but no green light (indicating it's charging).

I tested it with a fixed voltage supply (13.6V) and does not work. At a visula inspection, nothing is burn.

What should I check?

Thanks;)
 
Here it's the MBR. I removed the 2n6488 on the bottom right hoping they are the problem.

Before removing them, I measured the two TL494 voltage - supply was 13,54V
Bottom right TL494
Pin 1 - 0,006V
Pin 2 - 0,07V
Pin 3 - 0,07V
Pin 4 - 0,02V
Pin 5 - 1,52V
Pin 6 - 3,36
Pin 7 - 0,006V
Pin 8 - 4,08V
Pin 9 - 1,51V
Pin 10 - 1,19V
Pin 11 - 4,05V
Pin 12 - 12,84V
Pin 13 - 5,08
Pin 14 - 5,08
Pin 15 - 0,07V
Pin 16 - 0,006V

Upper right TL494
Pin 1 - 0,006V
Pin 2 - 4,79V
Pin 3 - 4,79V
Pin 4 - 0,01V
Pin 5 - 1,55V
Pin 6 - 3,51V
Pin 7 - 0,006V
Pin 8 - 30,22V
Pin 9 - 0,34V
Pin 10 - 0,34V
Pin 11 - 30,24V
Pin 12 - 30,25V
Pin 13 - 0,06
Pin 14 - 5,04
Pin 15 - 4,79V
Pin 16 - 9,14V
 

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I had finally time to re-assemble the MBR and test it with a battery. It does not work:mad:

The green led turn on but there is no output voltage.

The source is a fixed voltage supply running at 13,7V so definitely enough to turn it on.

I can only think the second TL494 (right side of the PDF) has problems as the first one is properly driving the 30V (actually, 30,01V)

I also checked the resistors (all) and all are as per the schematic - nothing burned.

Any suggestion?
 
It took some time but I finally got both e Q5 and Q6 replacements.

I changes both of them and is still not charging. :mad:

Actually, there is something at the output (around 12,5V) however it's not what should be as the working one has a higher voltage (13,3) with the supply at 13,6V
 
R13 (100 Ohm - pin 2 of Q5) has the same voltage at both ends that equals the output voltage - on both of them.

I'm using a good meter (Fluke 77) so it should be quite accurate

What is definitely different is the voltage at pin16 of IC2 - it's 3V in the working one and 0,06 in the non-working one

And the green light is lit on both - this is what make me crazy:(
 
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