I had exactly the same with my Datatool tracker. Although the tracker 'worked', mine was taking in the region of 60-70mA when sat doing nothing. Datatool offered to replace it for £125ish even though I still had a couple of years of subscription left, but by that point I'd just had enough. Their customer service is pretty rubbish.
I've always found a dc clamp meter pretty flaky to measure currents of only a few tens of mA. A good and quick way of testing for the current taken by the 'standard' datatool tracker installation without needing to mess with the battery connection and before pulling the bike to bits at that point is to use a decent multimeter which can read microvolts across the small red 10A fuse under the rider's seat. That fuse provides power to the tracker and one or two of the bike's auxillary systems. Using a sensitive enough multimeter to read the voltage drop across the fuse and having a chart correlating voltage drop to current for that fuse type and rating you can get a really good approximation of the current being supplied by that fuse.
The 10 amp fuse under the seat (bright red)-
View attachment 525584
Here's a clip of the chart used for the minifuses under the seat-
View attachment 525583
In my case a reading of 500microvolts or half a mV or so meant a current through that fuse of 60-70mA, and after disconnecting the tracker, that current fell to zero. The tracker was actually warm to the touch. Piece of sh!t. In my case the tracker worked and had an active subscription, but its battery or its charge circuit had probably failed so it was consuming significant current in its dormant non-transmitting state.
Helpful hint- If you do disconnect the tracker, you need to remember to plug the exposed loom back into the canbus termination under the seat.
Snooty I have a few photos I took as I was uninstalling mine including the cables, fuse and canbus term block. Let me know if you'd like them.
Rich.