There are a few steps along your MIDI signal flow that you can to check:
Are you sure the external MIDI controller is sending CC1 (on which channel). You can use a third party app like MIDI Monitor, that displays all the MIDI traffic going in an out of your mac
Is Logic receiving that CC1 MIDI Message. Change your Control Bar Display to Custom. It lets you see the incoming MIDI Messages. Here is a screenshot. The fader means CC, 1 means channel 1, another 1 means CC1 (Modulation), 82 is the value.
Record a MIDI Region while sending the Mod Wheel and check in the Event List if those data are recorded.
Make sure you don't have any filters enabled
On important thing. Check your Controller Assignments Window to make sure that the ModWHeel is not assigned to anything Any incoming MIDI Event that you use in the Controller Assignments Window will be intercepted and not recorded as MIDI Events in your Project.
Hope that helps
Edgar Rothermich - LogicProGEM.com
(Author of the "Graphically Enhanced Manuals")
http://DingDingMusic.com/Manuals/
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