Testing electrical accessories/ IR receiver
 

Greetings,
I'm trying to troubleshoot the keyless entry remote on my G320, which uses an IR receiver located in the rear-view mirror. I have located the other components in the system, and want to start ruling out parts. I've removed the mirror/receiver from the headliner and want to test it to see if it lights up (as it is meant to when it receives power but currently doesn't) - Is there a safe way to hook it up to a power source to test whether it works? I assume if I just hook it straight to the battery the amps will fry it- is there a way to regulate the amps to it? Thanks,
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