Bought based on a youtube review to use with our campervan. I tested it when I got it on our pickup tires and it worked fine. Couldn't use it use on an RV until rear window closed Measured OK once on RV, reported 0psi thereafter Checked locking air chuck, no obvious problems Tried other non-locking air chuck No difference Air hose removed and checked for clogs, they weren't there Batteries checked, you're loading the test well. So the only option now is to send it in in the hopes of a warranty repair But it costs as it's quite violent They say it's not under warranty The dial indicator air cartridge that came with our Viair compressor works very well better than this Pros: When it worked, it was easy to read . The chuck worked most of the time, but didn't fit the front tires. This wasn't the way to travel in an RV. I would not recommend buying this tool. Perhaps their non-electronic version of the dial indicator would have been more reliable.