A Washing machine tripping or fusing electrics is a fault you can't really deal with unless you have electrical knowledge, and a specialist insulation test meter. However, you might be able to do some basic checks as described in this article. A fusing washing machine can be caused by many different components, and many different wires or connections.
Most common causes for a washing machine fusing electrics
- The motor
- The heater
- The suppressor
- A wire shorting out somewhere
- Water getting onto an electrical part
Insulation test meter
To properly diagnose a fusing washing machine you need an insulation test meter. These meters put 500 volts (DC) through the appliance and individual parts.
They can detect the slightest of leaks to earth (low insulation faults). So this isn't a diy job. If you have the right equipment then you probably already know how to diagnose and deal with low insulation faults. If not, you should get someone in to look at it unless you can see something obvious like a chaffed wire.
If you can’t see anything it might be wiser to book an appliance repair
If you don’t have an insulation test meter
Without an insulation test meter you can’t do proper insulation tests, but it may be worth testing with an ordinary multimeter if that’s all you have. It should pick up a direct short to earth. For example, if you test for continuity between the heating element pins and its earth tag or any part of the metal on the element (remove wires before testing) there should be no continuity.
If you do get a continuity reading, then electricity running through the heater will find a path to earth. This will trip rcds or fuse the plug. The same applies to any other part such as the motor. There should be no continuity between any electrical connection and earth (or the metal casing of the part). However, if no reading is found it doesn’t prove there is no fault.
No continuity may just mean a fault can’t be detected. A continuity test (or multimeter) uses a little as 3 volt’s. It can’t jump gaps, or pass through high resistance paths. But 230 volts from the mains can if there is a fault. This is why a proper insulation test meter is needed.
Exactly when is it tripping the electrics?
If you don’t have an insulation test meter, and/or you can’t find anything with a multimeter, the next best thing is to try to get clues by observing exactly when the machine trips out. If it's as soon as you plug it in then it could be the suppressor (warning: suppressors and capacitors can give a nasty shock – even when unplugged).
If it only trips out after it has started filling with water and the drum first started to turn, then maybe it's a fault on the motor. (If you suspect the motor then it should also trip on spin).
If it trips the electrics a short time after it has finished filling with water and has been turning the drum ok a few times then suspect the heater. (removing the heater from washing machine).
If it only trips out on spin then it could be a bare wire in the wiring somewhere that's touching something metal when the drum is bouncing around. This can often be intermittent, only tripping with large loads when the drum bounces around much more.
Process of elimination
A competent engineer should be able to find the cause of this fault quite quickly. But without an insulation test meter it’s a different story. You can disconnect the washer from the mains and do physical checks for any snagged or disconnected wires.
Or for wires where the plastic insulation has been rubbing against something revealing the copper wire. This can short out if it touches something metal when the tub swings about on spin with a heavy load in.
If a part is suspected you can disconnect it to see if it stops the fusing. However this isn’t an ideal method. It could just trigger an error code.
And if it stops the tripping you can’t guarantee it means the part is faulty. For example, you could have a bare wire in the wiring harness to the motor which is shorting out on something.
You might disconnect the motor (moving the affected wire away from where it shorts out).
The washer no longer trips the electrics. So you buy a new motor at great expense. But it isn’t the motor.
The only way to truly test is with an insulation test meter. By the way they are far too expensive to buy to test one appliance. They are typically between £200 and £600 and carried by professional repair engineers.
If washer has tripped the RCD or fused – and now won’t work properly
Most people will naturally reset or replace a fuse and try the appliance again. If it fuses or trips again do not keep repeating this pointless cycle. Clearly there is something drastically wrong, which needs fixing. Especially in the case of physically blowing a fuse. If you keep allowing something to blow the fuse it can cause more damage to components.
Also, it would be very stupid to try bypassing a fuse!
Occasionally the washer might work OK and appear to have suffered no ill effects. If so, keep an eye on it. If it does it again try to observe when it does it as described above to get clues of possible suspects. If the appliance starts up – but with something not working properly – then it needs repairing. Whatever fused has failed completely, or damaged something else.
If nothing is working at all other than some lights it could be the main suppressor or main pcb. If the motor no longer runs it could be that the motor is the problem and it’s failed completely. However it could also have blown something on the pcb. Without the right knowledge and a proper insulation test meter you need to call in an engineer.
Fused and door won’t open
If the door won’t open and the washer has tripped the electrics it could have fused the door lock inside. This should only usually happen if there was a big flash, and maybe there isn’t an RCD fuse-board fitted (which should trip fast enough to not blow parts inside).
Alternatively it could even be the door lock that has tripped the electrics due to something shorting out inside (Washing Machine Door Will Not Open).
Notice how I keep saying, “could”? That’s not a good reason to speculatively by new parts. You need to be sure a part is faulty before thinking about buying one unless it’s cheap enough for you to be happy to take a risk on. And is also easy to replace.
Don’t get carried away
Over the years many experienced appliance repairmen have been seriously injured or killed.