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Here's the blown pcbReally sorry it's not zoomed in as this is the only pic I took of it
nasty. main burn up is a resistor, i can only assume Q1 probably a fet is s/c taking out R1 (500 ohm) ? They are not difficult to replace, but... U1 i suspect feeds the gate of Q1 via q2 & q3.I usually find after cold checks on components you can replace the obvious faulty ones but there will be further issues. In the past i have managed to repair some of the henry speed control pcb's, dc 24 and dc25 head pcb's etc - if the repair budgets are tight - more often though my customers are given price for replacement pcb which are usually accepted. If it was the other dc40 pcb then that would be a simple one, as its just a full wave bridge rectifier, smoothing cap etc - but yours is rather more complicated as we have seen. If you check u1, Q1 Q2 & Q3 using diode test / resistance you will find short circuit components. Board maybe a lot cheaper from someone with a connect account ? or from a person who has scrapped a dc40...Smd can be tricky, i do plenty as i still work for a panasonic retailer but it is becoming a tough old subject
The standard DC40 head has the DC24 motor in, the ERP one has the DC25 motor in. I doubt one would run the other in this case. Test the head motor with your meter, one often takes out the other.
Ahh :/I'm a proper amateur when it comes to complex electronics, circuit board stuff annoys me (once I touched a circuit board on a hoover purepower and shocked myself despite it not being plugged in!)I may have to just get a new pcbIf I use normal MK1 pcb would that be a bad idea? I presume the only difference is the soft start brush motorReplacing stuff on a PCB sounds too advanced for me :/
Your'e welcome, I am still 80% electronics at the moment and 20% vacs but need to reverse that figure when i eventually take the leap and work for myself.If i ever get one in with same fault i will attempt a board repair and document accordingly.As Dysonboy suggests try to leave an item switched off if it had a meaty reseviour capacitor, to spot them they will say for example 180uf 400v - reason it is 400v is the mains is 230vac but rectified full wave and brought up with the cap it will be around 320v to 340v dc. Modern power boards will have a resistor across the cap upto 100k usually and this discharges the cap for you when switched off - some equipment doesn't have the resistor and can stay charged for days. I always have a 100ohm resistor to hand with probes on to force discharge or a rather crude method is to use the metal screwdriver over the cap terminals.The capacitor on a dyson motor for example shouldn't hold a charge after power down as that's a different type of cap. If in doubt check it with a multimeter on dc voltage range.There are many variants of power supplies, and i still get caught out 33 years later !