I have not ever seen that as a failure mode myself but I would wonder if you have stressed the caps at all on the solder side thermally or either side mechanically. Have you been able to replicate the mode of failure by running controlled testing? Kat -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of [log in to unmask] Sent: Tuesday, July 01, 2008 5:26 PM To: [log in to unmask] Subject: [TN] Electrical Test Failures Fellow TechNetters I Really Need Some Help: I'm having a problem with a mixed technology PCB failing E/T for low voltage leaking.? The SMT components are mostly R's and C's with various I/C's.? The Thru-Hole components, besides various connectors, are IRF4905, Thru-Hole.? The SMT solder paste is aqueous and our process calls for three separate washes.? The PCB solder resist is LPI with a dull, matte finish.? Has anyone with aqueous experience ever had a problem with paste/washings leaving any type of residue which can cause a leakage problem? I thank all you folks in advance for your assistance. Bill Black Medco Tel?? 1 631 667 9699.? --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------