The 2001MY onward uses a ROLLING CODE RF keyfob transmitter and a single CR2032.
This info is for the North American market, I don't know about the ROW.

 

I bought a cheap transmitter tester but AUTO PARTS STORES will have a way to test also for customers.
Just bring the transmitter and ask if they will test reliable output. If the buttons are intermittent, you have your answer.

 

My UK 2000MY is the left fob there, so I suspect it's the change over was the same world wide.

 

 

I've struggled for ages to get my remote working, cleaning contacts, using an eraser on them, putting silver paint on them. All these ideas worked for a while.
In the end, I took the circuit board out, put it in a small plastic box on which I had fitted small buttons, and connected everything up with thin wire. Took a few hours to get all the connections right, but it now works 100%.
The box is small enough to put in a pocket or hand bag (for the ladies).
Pictures attached.
This can be improved on of course, e.g. get a proper battery holder and use a smaller box.
BTW, the original remote had 2 x CR2016 batteries, but this device seems to work happily with 1 x CR2032

Wiring inside

Finished, working device

 

I have repaired fobs in many ways as stated above. Cleaned circuit boards, Repaired and replaced the bubble switches and I have messed with the batteries and the contacts. What I have found is these are old and just worn out. Get a new FOB and go from there.
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