0V missing at the brush head motor

Ok had exactly this issue and it does appear that Dyson engineered the solution to prevent high current drain with stuck motors. Took mine apart and occasionally got some power to the brush head but normally no power at all. Maybe a dry joint on the PCB? I have no idea.

So I did a brutal hack. Turns out the +ve power is connected from the battery input to the power tap off whatever happens - but ground is switched.

From the photo, ground/-ve is the white wire. Handily right next to the feed from the battery. I dropped a big blob of solder across the wires, so now the accessories get the full blast from the battery when you press the trigger.

I really don’t recommend this fix, but it was (to me) preferable to giving Mr Dyson a few more £’s for his poorly made devices.

The V6 now powers the accessories “like new” and I’m not surprised. I think the motors are rated at 18v and now they are getting the full 22v juice from the battery pack!

I have the same problem.

I had zero volts on the brush head supply terminals and have cleaned and tensioned the connectors but still no power.

When the brush head is connected and I pull the trigger the vacuum starts then stops then starts again and continues with suction but the brush hasn't moved.

When I pull the trigger without the brush connected the vacuum starts with no stop and start again. Could this indicate a sensor stopping the power for some reason?

After assuming the power to the brush wasn't being given for some reason I manually rotated the brush and found it a little stiff even though there was no hair or the like tangled in it. I tried the power again and noticed it moved slightly then stopping again. I repeated a few times and it has started to work again.

I am now of the opinion that the power isn't supplied if the brush head motor is too stiff due to a fault or tangle, so after cleaning all electrical connections try loosening the resistance of the brush motor by giving it a few turns.

I have just put a tiny drop of wd40 to the brush drive bearing and it's working great. Fingers crossed, if it happens again I will be thinking it's the brush head rather than the supply which is disconnected at source to protect the vacuum.

I think that the Main Body PCB does not deliver the voltage if it does not detect a load - e.g. when a crevasse tool is connected. I found that when I used the mini-brush (also motorised) it started to spin. This meant that the main unit was okay and the fault was with the brush head.

I dismantled the brush head and found that one of the wires connecting to the motor, through the articulated joint had broken. There was enough play in the wire to allow me to solder the broken wire back together. I'm not sure how long this will last though as the wire moves around when the head rotates. I guess at some point I will have to replace the whole wire.

I have also had the problem whereby the dust accumulates at the contacts from the main unit to the dust canister. A pair of tweezers and some rubbing (isopropyl) alcohol soon sorted that.

I had same symptoms so I disassembled the head and there is a small Torx screw inside the plastic piece that spins the brush (pointed to in the picture below). After you remove the screw then you can pull the plastic piece off. There was a lot of hair that had gotten underneath that brush driver and once I had it removed the motor could spin a lot easier and the problem was solved. When putting the brush driver plastic piece back on don’t overtighten it. Check the spin is good.

Hi

Maybe check all the capacitors by putting one end of the multimeter on ground and one on the one side of the capacitor

If both sides beep (while on condinuity) you have a bad capacitor if one side beeps it is good

I have a DC44 Animal with the same problem. As an electrical engineer, I can tell you that if the power feed circuitry detects too much current (because of hair buildup etc) OR if there is no current (because of a broken wire or faulty motor), the voltage to the power head is disabled. That is why we see so many of these things starting and then stopping. In my case, I have a intermittent wire to the head motor that makes or breaks depending on the the position of the swivel head. Sadly, try as I might, I cannot open up the swivel unit that houses the slip rings which would give me access to the broken wire. Does anyone out there know how to do it? There must be a way, but it has defeated me and rather than spend more time on it, I have reluctantly ordered a new head unit.