Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4

[stj]

Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4

without drawing up a diagram i have no idea how that chip operates other than with the fan off it must be running at very low power to use a battery

[ezenia]

Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4

Found a cheap U1 chip on eBay. Replaced it and unfortunately the fan still behaves the same.

The LEDs are now behaving differently. When the fan is off and cable plugged in, I get the usual red faint rapid flicker LED and solid green LED. When I press the fan switch to turn on the fan, the red LED goes solid bright and the green LED goes off. This is with the motor disconnected.

Once I re-connect the motor, I get some different behaviour. With the fan off and USB cable plugged in, it's the same red faint rapid flicker LED and solid green LED. Once the fan switch is pressed and the fan spins, the red LED goes solid bright as usual, but now the green LED starts flickering quite rapidly.

I noticed that there are voltage drops as well with the motor connected. On D1 (pad next to S_R18), the voltage goes down to 4.3V for some reason. It's 4.63V on the other pad which is slightly lower than normal (usually reads 4.74V). On the motor connector + pad, the voltage reads 3.99V. When the fan is off and motor is connected, the voltage here is 4.74V.

I'm wondering if the issue is actually the motor now. If it the motor, I may as well give up because there doesn't seem to be a way to access the circuit board that's on the motor. I'm guessing it's glued in or something.

It's a shame if it is the motor. I wanted to fix this.

[sam_sam_sam]

Re: Suitable replacement IC? .PCB - X_BFJSFANRE_RLED_V4

Is it possible to hook up a incandescent light bulb instead of the fan and see if function correctly or not before you toss in the towel

Also is it to take a picture of the motor in question