700r4 converter not locking - Solinoid ok

Iíve got a í85 GMC van (6.2L dsl) that will not lock up the torque converter. Was at cruise speed under minimal load when converter unlocked and hasnít locked since. Have voltage at trans connector.
Solinoid checks ok with air pressure. Transmission doesnít appear to have vacuum line connected (never has since Iíve owned it) and vacuum pump has been inoperative for a long time anyway. Pan and filter are off now, would like to test further before reassembly. My knowledge of auto transmission repair is somewhat limited but if there are any reasonably simple diagnostic tests that can be performed here, Iím a pretty fast learner. Any help or suggestions would be appreciated.
Thanks
--
Posted using the http://www.autoforumz.com interface, at author's request
Articles individually checked for conformance to usenet standards
  Click to see the full signature.
Add pictures here
‚úĖ
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
700 does not use a 'vacuum line'
you should have 12 V at the 'A' pin, 'D' should go to ground when TCLU is commanded

http://www.autoforumz.com/Chevrolet-700r4-converter-locking-Solinoid-ftopict125894.html
http://www.autoforumz.com/eform.php?pa3407
Add pictures here
‚úĖ
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.