[rjnkanwal]

Finally fixed the dishwasher. I replaced the 100 ohm 3w resistor and tiny switch TNY264GN. Thanks to Dave and another user on one of the electronics forum, where they repaired the Bosch dishwasher by replacing the same components.
It took me so long because the TNY264GN I bought from eBay was dud. That made me think that there were other faulty components as well. I had ordered same time TNY266GN from China, which arrived yesterday and I soldered that one on the board and voila the dishwasher is working again. One can replace the TNY chip with the higher value and it will work. I learned this from the electronic forum and that’s why I used the TNY266GN. The other reason was that I got 5 of TNY266 for £2.

So two parts costing less than a fiver fixed the fault.

Thanks again Dave.

[rjnkanwal]

Don’t know about the chip? are you talking about TNY 264 GN or some other chip.

The register is definitely faulty. It is open circuit. I still have led flashing and apart from this, there is nothing on the display. I had almost ordered the replacement control module, direct from Bosch for £120 when I saw your other post from February and I decided to try the repair. If it didn’t work then no problem as parts are cheap. Thanks.
Regards
Raj

[rjnkanwal]

Hi Dave
I think you can help me on this. I inspected the main control board for any possible burn out or damaged component. There is a resistor, possibly 100 ohm which seems to be damaged. It’s coating is flakey and just like paint it is coming off, revealing the coiled wire underneath. It is reading open circuit. I saw another post where you suggested to replace this resistor along with tiny switch TNY264GN part. I just need a little bit more advice about this resistance to order the correct part. There are a lot of different type of resistances. To me it looked like wirebound through hole resistance. Am I right? Can you please advise? I gather from the other post that it is a 3w 100 ohm resistor but don’t know which type it is. Thanks
Regards
Raj

[rjnkanwal]

The time the check water and rinse aid lights start flashing, the dishwasher was in the middle of 29 minute quick wash cycle. Any info on possible faults will be helpful. Thanks

[rjnkanwal]

I was off today and off until the weekend, so decided to have a go myself. Saw a video on YouTube about Bosch heat pump. The guy showed how to test heat pump. So tested the resistance between two connectors next to earth and it is reading 20.9 ohms. He mentioned 20 ohms. I think I can say 0.9 ohm could be due to monitor accuracy or an error in my measurement. Well I can say that heat pump is working. Now back to square one.
Can someone please advise what possible faults can be when check water and rinse aid lights are flashing. There is no noise of anything turning on, the dishwasher seems completely dead.
Thanks

[rjnkanwal]

Ok I have now full working plug and mains lead without any short. I just removed the main power module and then tested it by plugging in each connection to find the short. There was none. Just playing with the power modules the short has disappeared.

Now I am back to the main fault, check water and rinse aid lights still flashing. Searching on Google indicates 2 faults, one with the main power module and the other with heat pump. Is there a test which I can do on the main power board to see if it is working or faulty.
Also if I need to access the heat pump, do I need to remove the bottom panel and how to undo the bottom panel please.
Thanks
Rjnkanwal

[rjnkanwal]

Hi Dave
Fixed the mains lead, plugged it into the dishwasher and before switching it on I checked for short within the appliance. Positive and negative terminal are showing short with 82 ohm resistance. With my limited knowledge about electricity I am little baffled. The knowledge says it should have been a complete open circuit which it isn’t, indicating short. Now if short then it should read zero on multimeter continuity test, instead it is showing resistance of 82 ohm. Do you think that power module is faulty or the heat pump?
Thanks
Rjnkanwal

[rjnkanwal]

One more question, can earth and positive be short and still work and cause heat without blowing up the fuse or it will blow up the fuse the second they become short.

[rjnkanwal]

Ok the second gang could be faulty, so I decided to try another socket. As there wasn’t any socket nearby, I used the extension cable. Plugged the dishwasher and turned on the socket switch and it gave the little bang and blew the fuse on the socket. Took the lead out of the appliance and checked for the short. The earth and positive are short in the mains lead. They don’t bring 0 on the multimeter, instead show resistance of 60 to 190 ohm depending which connector I measure from. Well lead is definitely short.

Now the question is that did the original fault of check rinse aid and water led came up because of faulty mains cable or the internal dishwasher fault cause the mains cable to get hot and become short. I mean each time I was testing the dishwasher the plug was getting hot and slowly slowly it may have caused the short inside the plug. Well I think the correct move would be to get the working mains cable first and then see what happens. Thanks

Rjnkanwal

[rjnkanwal]

Hi Dave
I am not aware of plug theory. What do I need to check? Searching online about plug getting hot doesn’t bring the desired results. Most posts relate to when appliance was in use. I did think about the socket. I ruled it out as washing machine is plugged in to the same dual gang socket and while using washing machine the plug doesn’t even get warm.
The dishwasher plug is a moulded plug so can’t check the state of wire inside it.

Although I didn’t measure the current on the PCB but I assumed it is there as LEDs are lighting up. Thanks for your reply

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