Control Board Of LG Washing Machine Restored
The control board of this washing machine was brought to me by a regular customer, who wanted to know whether it could be repaired as the company technician who came to attend the complaint said that it was defective and replacement would cost a fortune!
You could perhaps make out that the board looked very dirty as it was a home for cockroaches and it had spoiled many parts including jumper wires that got rusted. I carried the board to my techie friend who runs a shop about 5 KMs away from my home, as he was focusing only on Washing Machine, AC. Microwave Ovens, and Fridge boards and accepted only the work given by the technicians and not from public.
He had arranged a set up for testing the board for all functions like water pressure sensing, motor rotation clockwise and anticlockwise and all modes like rinse, spin wash etc. He had dozens of such self-made gadgets for almost all models and it was therefore easy for him to test the board without the need for moving the whole machine. As he was busy, I left the board there and returned home.
He reported that a few components were found burnt such as the rectifier diodes and he replaced them. But the uController was not functioning. He had cleaned up the entire board thoroughly and on checking the voltages at the pins of the crystal, it was not in order. So, he replaced it. But even then it did not work. When he checked the supply voltage, it was found jumpy, which he traced to a jumper wire that was making poor contact due to dry solder. Once he retouched that portion, the board responded and got switched on. Then he cleaned all controls and connectors. The uController is housed behind the control unit and it had to be peeled out from the glue. Then the suspected areas had to be pierced removing the thick coating of silicon sealant. Let us have a look:
The board functioned well when he checked all modes. After applying the sealant once again on the portions where these were removed, he fixed the board back. Following are the pictures of its workings:
The board was sent to me next day through another technician who had gone there for a similar work getting done. The customer was very happy that the board got repaired and thanked me for the quick service. The customer also offered me a Sony LED TV for service. A successful repair brought another one for me!
Was there an excuse for the satisfaction for not getting added to the collection? No, never and it did get collected as usual without fail! (LOL)
This article was prepared for you by Parasuraman Subramanian from India. He is 74 years old and has more than 30 years’ experience in handling antique equipment like Valve Radio, Amps, Reel Tape Recorders and currently studying latest tech-classes conducted by Kerala State Electronics Technicians’ Association. He has done graduation in BBA degree, private diploma in Radio Engineering and retired as MD of a USA company. Presently working as Consultant to Hospital and other institutions.
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Waleed Rishmawi
March 1, 2025 at 6:27 pm
thanks for sharing. yes I relay hate the silicon coating they cover the board with, I know it is for a good reason but that does not help to do any kind of repair on. I am glad it worked out. thanks for sharing and have a blessed day
Parasuraman S
March 1, 2025 at 8:49 pm
Yes, dear the silicone coating is a real pain! Many thanks!
albert van bemmelen
March 1, 2025 at 6:56 pm
Only those very experienced engineers that deal on a daily base with such special brand of machines are capable to master and fix these repairs that often involve multiple causes of malfunction. These repairs also require special made test tools to cope with the many differences in design that exist.
Sadly even when a washing machine is completely working with no defects on control board or motor or other electronic part, it still may mean the end of life for the machine. Like when my washing machine sadly had gotten an internal leakage causing a low current flow between the earth wire shorting to the heater element. That often caused my earth powerfuse protector cutting the powerline which couldn't be fixed because of the rust on the exposed internal metal housing.
Parasuraman S
March 1, 2025 at 8:58 pm
Here, we have facilities for metal and fibre patching. I have done it in my car also. Many technicians get such patch work done locally for costly refrigerators, washing machines and aircondioners. Many thanks for your comments, dear Albert!
YOGESH PANCHAL
March 1, 2025 at 10:54 pm
Good Job!Sir,
Waterproofing on the PCB is must for this device & Technicians who work on washing machines are used to for the process of cutting the PCB Unit from the Backside (Not from the sealant side) to reach the solder Joints & also these PCB required different loads Sensors for testing.
You made the right decision in hiring an expert to get the job done.
Parasuraman S
March 2, 2025 at 7:33 am
Many thanks for your analytical comments, dear Yogesh Bai!
Mark J
March 2, 2025 at 4:34 am
Parasuraman thanks for sharing.
Parasuraman S
March 2, 2025 at 7:34 am
Many thanks, dear Mark!