1769-OB32 problem

Hi Gents:

I met a problem with one of my 1769-OB32 module. Some of the channels suddenly malfunction -- The light indications for the channel are showing right status for ON/OFF, but the output voltage is wrong. When I force channel off, I can get 24VDC from the terminails, while when I force it on, I can measure 18VDC. Meanwhile, most of other channels are working right, that no voltage when off and 24VDC when it is on.

Any thoughts? Thank you.

Sounds like that output transistor has failed, you can either move the output to a spare that works or replace the card.