Friend we have a haier non inverter ac pcb which we got for repairing what is the fault with it let me tell you? that it's remote is not working on it it is conventional ac and its remote is not working we have to switch it on through the button it is a big problem because in today's era everyone wants easiness so let's repair it and see what's the problem with it and one thing more before coming to me it has gone to another workshop for repair a lot of work is done on it someone has tried to repair its solder mask as he thought that wire could have been damaged somewhere and tried to repair it but he couldn't repair it now we will repair it and check where is the fault first of all, I will one it and check whether it is happening or not I have installed a transformer with it because it had no transformer with it we will install it all three lights are working it is glowing for some time then stops as remote is not working i will on if through the emergency on/off button its red light is working i am tryign to on it through the remote but it is not working through remote now let me check whats the problem this is its display and it has an IR sensor in it this IR sensor receive the signals and shift the complete program to mirco-controller but you can see some one has worked on its PCB But i think it has no fault you can see a capacitor is installed with it the capacitor is full of rust the IR has also rust on it now let me open its cover and see it from the bottom because I have doubt it is rusty as well let me clean its capacitor and change the IR sensor if possible then see what happens after this it will work I hope so I have removed its cover from the back and see it is full of rust so, first of all, we clean its rust and after cleaning change its parts and check its working or not if not working then we will check its further circuit the PCB is fixed now and it has no problem with it because I repaired it but How? let me tell you that as well first of all, let me tell you what parts I changed to it and what was the problem with it and what did I do this is its display so you can see in it I Changed the IR sensor which was too rusty the capacitor was also rusty I changed it as well now what was happening with it see let me show its center point is ground the right side is VSS And 5 volts should pass through it the left side pin is IR output and then this IR sent signals to micro-controller works this way and whenever I got a chance I will make a video on the IR sensor and how it works what was happening here let me tell you and what was the reason it was not working someone tried to repair it but was unable to do it now let me tell you what was happening I will hold this PCB now you will say I didn't check it for you let me check it at the last l will switch it on from far I have on it but, I will check it THE LAST AS WELL now let me show you what is the problem so normally as I told IR sensor input & output it has a transistor installed here which is an NPN transistor the 5 volts were coming here and this is its ground when I checked it 5 volts were flowing means output had 5 volts flowing but IR signal also need 5 volts two resistances are installed of 331 approximately 23k-ohm but now I have installed 22k-ohm and when I was checking volts on resistance input 4.7volts are showing but before this volts were not available here the resistance here seemed to be ok this is a 330 ohms resistance and was looking fine with multi-meter but when I changed it I got ok because the voltages were not coming here as it was showing voltages on the NPN transistor which means that these resistances were faulty I have changed them both and it is ok now let me show you from another side that how is it working let me show you it checking we have installed the motor as well the indoor motor is working right now and let me show you its lights as well I will switch it on this way it is off now now pressed the power button it is on now the light has also been on, and this way it's working.
and the PCB had no remote control working on it is ok now..
