Drivers and tailcap readings

Help me understand something about the relation between a driver's output current and tailcap reading...

Today I put a new driver to my broken UF A10, I think the driver has 3xAMC7135 @380mA each (1 mode)... I put a freshly charged 14500 in (4,19V), take a tailcap reading... and it shows 680mA... isn't is supposed to be close to the 1140mA of the driver?

I am making tomorrow another driver replacement to my UF V6-T60 and will see how close the tailcap reading will be to the driver's 8x380mA...

Unless for some reason since I replaced the fuse in my DMM, it can no longer take accurate amp readings (could this be a possible cause???)...

The answer is probably burden voltage over DMM and probes and voltage sag in the battery.

I just installed the other driver I was talking about it's rated at 3040mA, and taking a tailcap reading on high gives 3000mA which seems in line with the driver's output... so I am wondering... is it possible that on the first driver that I swapped, one of the AMC's is kaput, and is only working with 2 out of the 3?

Your cell could be kaput, too.

Cell is barely used, and I tried 2 different cells, same outcome...

In the case you descibe it would seem that one of the 7135’s is not working since the consumption is so much in line with a 2*7135 driver. Maybe you can try to go over the drivers soldered joints? Hope you get it sorted out.

Probably that was it. I swapped with another driver and now I am getting ~940mA tailcap reading, consistent with the 3*7135 of the driver.