One of our vehicles has a spare key which has only worked for door locks since we got it. Will fit the ignition but won't start the vehicle. Well took a closer look today and noticed it says that it contains a replaceable battery, but when I open it up it's empty. This is labeled as "Ilco eh3." Googling does bring up some various people struggling to open the key but I can't find any info on what battery type to look for or where to find it...
