Parasitic Draw Unknown Source

Not one that will test wires that small, or I guess be sensitive enough to read mA. Can look into that though

 

In multiple vehicles that I have helped to troubleshoot over the years, it was always the radio. For some vehicles, the radio would randomly NOT shut off (or would possibly "wake up" for some reason) when the vehicle was turned off. Modern radios are connected to both continuous and accessory battery, and many can be turned on by both the front panel radio controls, or even by canbus signals from the BCM or ECM.

If it is an intermittent failure (as it seems to be), try pulling the radio fuse for a few weeks and see if the issue still occurs.

 

dont know if matters on op truck but mine will shut off whatever ever is draining battery after 30 mins.....like if the dome is left on

 

Not going to be the case here, as it's something staying on, not over-drawing.

 

I've had some success using a thermal camera but it only works when the vehicle has been parked overnight so everything has cooled to ambient temp, anything drawing power will be slightly warmer and will show up on thermal but if it's covered up by something you won't see it. Worth a shot though if you have access to one.

A standard DC amp clamp will pick up 300mA, under 100mA they typically don't work.

Have you looked around under the dash for any aftermarket nonsense that may be tapped into something?

 

IMHO, the best tool for the job

https://www.powerprobe.com/na/en/product-list/content/89C9e41Fbb5E

It isnt cheap but think of it this way, what is your time worth?

 

That only tells you if you have a draw (which we know we do) and how much it is (which we also already know (350mA). Just an alternative easier way to check for a battery draw, doesn't really help pinpoint what's causing it.
Battery parasitic draw can be one of the worst things to track down on a modern vehicle, there is so many possible causes plus you can have one thing keeping other stuff awake which really can make it fun.

 

test with the fuse removed. remove one fuse at a time but do not put it back in...just keep going until draw goes away. DO NOT PUT FUSE BACK IN AFTER CHECKING

 

and don't lose track of which fuse goes where