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Discussion Starter · #1 ·
I've always been unimpressed by cooling on the 2500. Fan operation cannot be manually switched on due to firmware problem apparently. Rack mounting has necessitated a solution.

I've reviewed the circuit of a RX-V2400 and found close similarities in the design, and made a hardware mod that make the fan run full time.


The fan is 24V and connected to the POWER board (exposed mains - BE VERY CAREFUL and don't take off the cover if you don't understand what your dealing with and that you can KILL yourself).

There is a small DC power supply on this board. It does NOT supply the fan. A 34v supply to the board from elsewhere does.

Transistor with large HS on this board controls the fan.

The CPU on the MAIN board switches +5v via 4k7 resistor to the FAN line into the POWER board.


The MOD is shown in the photo attached (NOTE labels are incorrect FUNCTION = MAIN referred to in the text. This board is on the opposite side to the power supply).

The FAN line to the MAIN board is CUT and connected to +5v via a 4k7 resistor spliced into a +5v line.

Fan now runs continuously.

With the power disconnected and cover off, you should be able to confirm the above lines and make the MOD since the connectors on the board are clearly labled.


It would also be possible to control using the 12v control line and a small relay to switch this line.

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