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Hello,

The Key fob on my 2015 Volt is making a steady, loud ticking noise, like a wind up watch. Has anyone else experienced this? Everything still seems to be working fine but it sounds like that even when not in use. Any ideas?
 

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That's a new one on me. Try removing the battery, then putting it back in to see if the remote still makes noise.
 

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That's impossible. I've taken my 2015 remote apart. There is no noisemaker inside. The sound must be coming from something else. Does it stop when you remove the battery?
 

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The only way a fob could make noise like that is if it is electrically arcing.
 

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Ash Castle? Nah, that doesn't sound like a fake name at all:

170728
 

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From what I've seen in the movies, throw it into the nearest bucket of water and run!
I like that thinking :oops:, but no, it's very simple.

After I (accidentally) washed a fob with the laundry, I discovered it wasn't working any more. I tried replacing the battery, but no joy. Time for a tear-down....

My key fob seemed to be working. It was powered by a 3V CR2032 coin cell (as many fobs are). After a bit a probing, I found the 3V from the battery was boosted to 12V for the transmitter with a boost-mode switching converter. The chip (a microcontroller apparently) was operating to maintain the 12V source, but had lost the codes it needed to open the car doors. When I pressed buttons, the transmitter would be keyed, but nothing was being sent.

Mr Castle's (any relation to that mystery writer Rick Castle?) fob is maintaining its boosted supply for its transmitter. Leakage through the output capacitor drains away it's charge, which must be replaced. The boost converter starts up for a few msec to recharge that capacitor. You might hear that as a tick.

There are several components that might react to that start-up. Ceramic capacitors sometimes behave as a piezo-electric crystal. The ferrite (powdered iron) core of an inductor (coil) can also generate noise (remember that high pitch noise that came from your CRT based TV?) You'll likely find both inside your fob.
 
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