Background
My neighbour was having problems with his TV and remote control. It would not turn on or off reliably via the remote control nor change channels reliably. He tried changing the batteries but this did not help. I said i would have a look at it.
The batteries were in deed in good condition. My neighbor used the TV in the kitchen and the state of the case gave me a few clues to what could be the problem. I popped open the case and the inside could only be described as a bio-hazard area!
The batteries were in deed in good condition. My neighbor used the TV in the kitchen and the state of the case gave me a few clues to what could be the problem. I popped open the case and the inside could only be described as a bio-hazard area!
After popping open the case i removed the circuit board and the rubber membrane keyboard.
There was a lot of dirt, food debris and oil on the rear of the membrane keyboard, the inside of the case and on the button contacts on the circuit board.
It was clear that the oil and grease on the circuit board and button contacts was preventing a good contact stopping the buttons working correctly.
I cleaned all the removing the dust and debris with a stiff brush.
De greasing agent was used to remove all the oil and grease which had run under the keyboard onto the circuit board contacts. It was also used to clean the keypad buttons on the rear of the keypad.
The keypad was reassembled and successfully tested. The TV can now be reliably controlled via the remote control.
Just a few minutes work prevented another perfectly serviceable TV from being sent to the scrap yard.
Update 6th February 2015
Just as i thought it was safe to assume that the repair to the TV remote control had been successful and was working properly it started to misbehave again! I dismantled the case as before and examined the key pad. There was very little oil and dirt so the problem was probably different this time. The repair outlined below took less than 30 minutes.
Closer examination of the on/off button showed it was clearly more worn than the others as can be seen from this picture. As i had recently repaired a crossword puzzle device by replacing a worn out button i decided to try the same with the TV remote.
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I carefully removed a conductive pad from a donor keypad which had been little used.( An online banking security keypad.) I removed the worn out conductive pad from the TV remote and carefully glued the donor part in place using super-glue. After a few hours to allow the glue to set fully the TV remote was re-assembled and tested. It worked as it should with no need to wiggle the button to get it to work!
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