Using the same 3145 Innova on my '90 SC Anny, just now, I connected it to the red connector, then key on, then reader on, then hit the test button.
The display showed 00 and the 'link' icon lower right. That's all. With it and the key still on, if I pull the connector off the reader, the reader shows the small black square icon on the right with no link icon. This process is repeatable. I have no issues w/my ABS, and assume the code reader is talking to the system, but has nothing to report.
Note while I've done my share of ABS repairs on my Anny, I've only used duffy's webpage to troubleshoot. In contrast, I have an OBD-II reader I use on my 2002 Windstar that has provided distinct ABS info I couldn't live without.
If you care to try it, instead, there is a manual jumper method that lets you read codes via flashing cluster light that lives on TCCoA:
http://forums.tccoa.com/45-brakes/69004-reading-abs-codes.html