Samsung Fridge Fan Test – Bench Testing a Three Wire BLDC Fan Motor (no refrigerator required) Video Transcript
In this video I’m going to show you how to bench test the Samsung BL DC fan motors or brushless DC fan motors so I got a few different Motors here they all run on 12 volts uh they all have three wires and the wiring color is all the same on all three any of the Samsung um DC fan motors I’ve seen all seem to have the same color wires the black red and white so here we have a condenser fan I’m not even going to test this one because I know uh some varmint got in there chewed the wires up on it I know this one’s no good um no point an even testing that one this fan here is a I know it seized up it was making noise and seizing up we can try testing that and see what happens and then this one here I know is a good fan out of the fridge section so let’s start with the the freezer fan motor so again we’ve got our red white and black wires red wire is 12 volts DC from the PCB to the fan motor black wire is going to be 12vt negative coming from that main board or PCB to the fan motor these are the two that are going to make it spin the white wire is a feedback signal this sends the RPM or the fan speed back to the PCB to let it know yes I’m spinning if it doesn’t get the signal back it will pulse the fan on and off several times before giving up and it’ll give up for about 10 minutes before it tries again to get that fan motor going so don’t get fooled with that because sometimes the PCB is actually disable the power to it so you might be testing for power coming from that main board of this fan and you may have nothing uh but it’s because it was been disabled because the fan itself is not spinning or it’s not seeing it spinning so anyways let’s get to bench testing so we’re going to bench test this fan it’s a 12vt fan but we’re going to bench test it with a 9V battery we’re low DC voltage here so we don’t have to worry about getting any shocks off of this you can touch across here no problem it’s not going to hurt us all right so we’re going to go black to black red to red and we should be able to fire that pan up so red black and doesn’t want to go um I’ll make sure that I have voltage there 8 volts pretty close to nine oh it’s trying to go there there it goes so fan will spin but we know this fan is we got the good one let’s try the good one out here get rid of this guy okay same wire colors and I know again this is a good fan good fan motor works was working in the fridge so I’ll connect my red to red black to black black to negative red to positive and our fan spins so we know this is a good fan it’s capable of spinning what we don’t know is are we getting a feedback signal on this white wire if you were testing this in the fridge and the fan was spinning you should see that 5 Vols coming from the main board on this wire being reduced the faster the fan spins the more that voltage is going to be reduced coming back to the the main board right but we can bench test that and get an idea of what’s going on that way as well so what we’re going to do is take our meter here we got the meter in view we’re going to go negative onto that white wire positive to positive and then we’ll get the fan spinning we got over 5 volts happening there but remember this is a 5V reference we’re using a 9vt battery the numbers aren’t going to be correct uh it’s just kind of gives you an idea of if you’re getting any kind of signal on that at all now I’m going to Jam this fan up and try it again so now we’re up to 8 Vols but again like I say we’re working with a 9vt battery here so in the bridge that would be closer to 5 volt you’re getting 5 volts on that feedback signal and the fan is spinning uh there’s all a problem with that circuit depending on where you’re testing it or the fan itself the hall effect sensor in the fan is effective take that out spin it up again we’ve got about 5 [Music] volts again voltage numbers are going to be off because we’re using a 9vt battery and it’s not getting that 5vt reference but it still gives you a good idea of what’s going on there with this uh we’re we are getting a signal on this line so this is a good fan head on over to ApplianceTechInfo.com for more appliance repair information and if you enjoyed this video don’t forget to like And subscribe