Google has recently disabled the ability to send directions or addresses from Google Maps to Telenav GPS devices.
Google's Daniel Mabasa from the Maps team confirmed the feature no longer is working but said he cannot comment as to why. Here is what he did say:
We can confirm that the Send-to-Car feature is no longer available for Telenav. We aren’t able to comment on the details of our ongoing partner relationships, but the feature continues to be available for many other partners such as Garmin and others.
So clearly there was some sort of partnership agreement that did not end up renewing upon renewal.
Who's fault was it? I won't venture a guess.
Forum discussion at Google Maps Help.