In the version Google Maps javascript API 3.18, a bug is introduced that will cause the controls on the map to disappear in Joomla 2.5.x. Too bad this version is launched as live/production version on 21/11/2014 and so the bug introduces it to all live sites.

This is solved in version 3.3 of Joomla plugin Google Maps. Request for this version and test it to so we can publish it soon..

The bug is actually in mootools or prototype etc libraries. The version of mootools in Joomla 2.5.x has this problem, but it is solved in the mootools version of Joomla 3.x.

So upgrading to Joomla 3.x is a good solution especially because the support for Joomla 2.5.x is stopped.
An alternative is to replace the mootools of Joomla version 2.5 with the Joomla mootools of version 3.x.

You can solve it temporarly by setting the google maps api version to 3.19 (and not 3, 3.x or 3.exp) so you use the latest development version of the API. This introduces a new bug that the control icons are on top of each other.
29/01/2015 UPDATE: Google is working on this problem in 3.19 before 3.17 will be deprecated, see issue tracker. 
07/03/2015 UPDATE: Version 3.17 does not work anymore and the bug of missing controls is in the version too.
08/03/2015 UPDATE: Solved in version 3.3 of Joomla plugin Google Maps. Request for this version and test it to so we can publish it soon.

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