HELP! The Features of My Layer Don't Show Up!

[SSMGroup]

I needed to upload sewer lines and manholes to ArcGIS Online.  The manholes zipped shapefile uploaded fine.  The sewer lines, however are not.  There are about 600 sewer lines, so the amount of data should not be an issue.  Every time I upload to zip to ArcGIS Online the new layer is there, but there are no features! In the attribute table, I see all of my fields, but again, there are no features.  What is the problem?  This file was originally taken from CAD, then imported into ArcGIS Online.  Every thing was perfect in ArcMap, so I don't understand what the problem is.   Any suggestions?  Does anyone have a similar problem?

[DanPatterson_Retired]

The coordinate systems are different and/or they are undefined.  Find out what they are.

[SSMGroup]

They have the same coordinate system.  I even did a "zoom to" (assuming that was the problem), and it doesn't zoom to anything. 

[MichaelVolz]

Can you load each CAD data set into ArcMap separately, then load the other data set, and see if the projection of the data frame is different depending upon which order you add the layers to ArcMap.

[SSMGroup]

Well, I just created a new layer and traced it told the previous one.  I uploaded that, and it worked.  If I find out what went wrong, I will let you guys know!