Luxman r115 remote. Transmits signal but receiver does not react

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Have 2 r115 luxman's with remotes. One remote works.
The other had some corroded battery. When u press buttons red light on remote flashes. But receiver does not react
Not getting the signal. Receiver reception is fine as the working remote works fine with both receivers.
I swapped a transistor between remotes. Led light. Capacitors. Haven't touched diodes or resistors.

Nothing changed. Can nec d6122g 001 chip be the problem? Where can I buy the chip.

Or is there some remote reset procedure on luxman's
 

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As you say the working remote controller works OK with both receivers, the problem must lie in one controller so how about some fresh batteries for the non-working unit and carefully inspect its PCB with a mag. light or loupe, including keypad switch contact faces and tracks for damage (possibly from the leaked electrolyte) and cleaning up generally, as necessary. The controller chip is unlikely to have failed and most problems will be with the tiny tracks and soldering, microscopic corrosion, worn switch contact faces and physical stress on the case.
 
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Hi Richard,
Try replacing the contacts. You can find new ones listed at Digikey or Mouser or some other parts vendors.

The other thing you should check is that the ceramic resonator (used as a crystal for the processor) hasn't been broken or has cracked contacts. Swapping parts between devices (remotes in this case) is a great way to end up with two non-working items. It might be helpful to connect an oscilloscope to the resonator and ground (batt. neg terminal) and key the remote while watching the 'scope. Try it with the working one first and set it for some kinf of display, then check the dead remote. Also make sure non of the corrosive materials made it to the main board. That stuff is conductive and can cause a microcontroller to misbehave.

Take your time and examine the remote under a bright light and magnifying glass. Then make sure that full power is making it into the PCB.

Good luck, Chris
 
Batteries are super new. I've never seen batteries newer than what's in remote now.
Someone may have had batteries reversed at some point.
I looked pretty close.. no cracks. What are the most voltage fragile components? I am still leaning towards thenchip issue.. I'll look for this nec chip in other remotes..seems like nec chips are used in all remotes.

Need to check if it's sending any infrared signal. Good call
 
Open circuit IR (infra red) diodes are a reasonably common failure item on any remote.

If it uses a chain of series IR diodes then any that are faulty will have adifferent voltage across them. If they are in series then as a test you can short the suspected one out. Old scrap remotes are a good source of replacements.

Diodes, ceramic resonators (as Chris pointed out) and liquid contamination are pretty much the only faults that occur with remotes. I must have had close to 5k plus faulty remotes pass through my hands over the years. Maybe more.
 
Problem solved.. it was a very hard to spot broke Connection by one of 4 diodes. I had to scrape off some solder Flux left by previous owner.. and a little board casting to clearly see that thin copper connection was broken.. see pic. Now remote works
It was extremely handy to have a working remote.. to pin point that particular diode connection. )
 

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