Chosen Solution

Hey everyone. So what I’ve got here is something a friend of mine handed to me to fix since it stopped working when she tried to replace the battery, and isn’t prepared to pay the outrageous price it costs to get a replacement one. I’m not sure exactly what the car is (probably Mitsubishi based on the logo). Nor do I even know the model of the remote (please check the pictures), but JX331BA seems like a half arsed guess based on a Google search. I also tried battery testing both battery cell coins however I believe they are both fine. I think the problem is the battery connectors, but I don’t know exactly how the contacts should be made to fit so I’m first hoping if someone can track down a picture of it. Also, advice on the smartest way to repair it. Edit 1:

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Hi, Are there two batteries in the key fob? Were they sitting on top of each other e.g, -ve face down on both to give 6V between the connectors? If there is only one battery in the key fob as is usual with key fobs, perhaps the easiest way to repair it is to unsolder and remove the old battery connectors from the pcb and clean up the board terminals and then solder a CR2032 battery with leads - example only (as long as it fits in the case OK that is) You can also try this option and connect it to the key fob to test if it still works or not, before getting a replacement CR2032 battery with leads(I don’t know if it will physically fit into the case but you can use it to test if the key still works ;-) Unfortunately it is not shown on the board which are the +ve and -ve battery terminal connections on the board, but I’m thinking that there should be reverse battery protection built into the circuit to allow for when people re insert a new battery back in, in the incorrect way and it doesn’t work and they have to reverse the battery to make it work.

If the central locking stopped working after she replaced the battery it is possible you may have to resynch the key to the car as the radio frequency may have reset. Follow the below steps or look up resynch my key in the owners handbook :- 1- Insert key into ignition 2- Turn key to position 2 (radio on engine off) 3- Press and hold any button for a slow 5 count 4- Remove key from ignition and try buttons PS DONT go to a dealership if you do end up replacing the key.  Other businesses will charge upto 70% less. Good Luck