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Fixing a dishwasher...?

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experimental

New Member
My dishwasher died and according to a service guy it's probably one of the cables going from the control unit down to the machinery (the machine works through 90% of the cycle, only fails to pump out water at the end). The problem is, where I live services are expensive as hell, so it's more economical to buy a new machine rather to have someone dismantle the whole thing to replace a single cable.

The cables are rather hard to access - running from the control unit in the door, through the door to the main chassis - so I can't just try both ends of each of them with an ohm meter to see which one is broken. Is there another way to figure out which one it is, then try to fix just that one?
 

Les Jones

Well-Known Member
Most Helpful Member
Have you checked that the drain pump is free to turn ? Also you could connect a neon indicator lamp in parallel with the pump to verify that it is being powered on at the end of the cycle.

Les.
 

Musicmanager

Active Member
Morning Experimental, welcome to ETO .. .. .. ..

Before you embark on a lengthy search for a faulty cable .. ..

IMHO it's much more likely to be a mechanical problem than an electrical one .. .. 3 things to check ..

1. Check that the drain hose, usually ribbed rubber is not either clogged or kinked in some way preventing drainage. Dishwashers don't drain particularly quickly so even a partial obstruction may give a problem.
Also, there is a drain filter inside the tub - checked that is isn't clogged or obstructed. They are usually on the bottom panel of the tub to one side. If your machine is a Bosch, it may be underneath the bottom panel.

2. Check that the Drain Valve is operating .. .. usually the drain hose is attached to the drain valve with a hose clip.

3. Check the pressure switch; If this switch is faulty the machine will not know there is water in it. These come in a variety of shapes and sizes, googling 'dishwasher pressure switch' will give you some idea. It can be identified by a small tube attached, often clear plastic. Easily checked by removing it and blowing into the tube inlet - listening for the click - but CAUTION .. if your tub is full of water pulling off this tube will drain it all over your feet !

If all of this is OK, then you're more likely to have an electrical problem.

I hope this helps

S
 

experimental

New Member
The weird thing is, it would randomly work, but fail most of the time. A faulty pressure valve does sound like a possible culprit, I'll try to find that first, thanks!
 

alec_t

Well-Known Member
Most Helpful Member
Easily checked by removing it and blowing into the tube inlet - listening for the click
If that tube gets clogged the pressure switch, and hence the pump, won't operate correctly. A common culprit with washing machines.
 

AnalogKid

Well-Known Member
Most Helpful Member
To me, intermittent smells like a failing connector. Those usually are quick-disconnects, or "Faston". On the solenoid or the drain valve will be two tabs either 0.187" or 0.250" wide (3/16" or 1/4"), with mating connectors pushed onto them. If one of them is loose or the metal surfaces are corroded, that would cause an intermittent connection that changes as the dishwasher vibrates.

ak
 
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tcmtech

Banned
Most Helpful Member
As mentioned earlier, look at all of your connectors in detail from the main control switch/timer device down to whatever pump and solenoids it controls.

The vast majority of the time things come down to a bad connector or wire someplace. Either the two pins/connections inside a wiring harness socket or plug are bad or one of then has a bad crimp underneath it or a wire has been bent so many times (where it passes in and out of the door) it has failed inside its insulating jacket.

If so you can, just add a jumper wire to bypass the bad connector, or if your handy enough and capable of doing such work, replace the actual connection ends inside the plug and socket set if the plug and socket bodies are not melted or damaged beyond reuse. That or pull a whole new wire though the unit.
 

pfofit

Active Member
We need model #, Dependant on age it is either a separate electrical pump(newer) or built into the sump by reversing the main motor and various valves balls or flappers. (older).
The newer ones with your issue are nearly always
1. bad solder joint on the control board for the pump or
2. a pinched drain hose or blocked drain where it connects at under the sink or
3. bad/plugged pump.

The pumps have a magnet attached to an impeller, this isolates water from the electricity, they can wear (running dry to long, the water is a lubricant ) which causes them to go cock-eyed and jam against the wall in their housing.
The control board, depending on company and or age, either uses a relay or a triac to power the pump from hot/L1. Typically one side is neutral.
The broken wire at the door hinge point is rare on newer models but was common 20 years ago. They have better cable troughs at the hinge point to protect the wires.

cheers
 

KJ6EAD

Active Member
There's a lot of brand and model specific troubleshooting guidance available online; some of it from companies that sell parts.
 

experimental

New Member
A quick update: I dismantled the thing and it seems most building parts are integrated into a single unit. The only external building parts are pump, heater, hot air fan and overspill detector. So if the problem is with one of the parts on the integrated unit, the whole thing is toast.

That said, now suddenly it doesn't want to fail. I would not call it repaired, but currently it does its job
 
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