Hi all,
I have had my APM1 working perfectly for quite a while but now i screwed up... I accidentally touched the Battery Voltage Monitor pins* the wrong way around to the battery balance lead. It was only for a fraction on a second but I saw a small spark :-(.
Now the APM1 only works when connected via USB. Both APM1 and oilpan function as expected**. But if I connect it normally to battery nothing lights up on the APM1 or the oilpan. At first the APM power LED lit up only but now not even that.
The PDB outputs 5V as it should so the problems is after that.
My hardware is exactly the 3DR ArduCopter Quad-B kit
* I am using the built-in voltage sensor
** Connect to mission planner, all sensors working
Any ideas?? I you give me a solution where I get it flying tomorrow I'll buy you a beer, or seven, when you come to Finland... :-)
Replies
In regards to one of your previous posts where you have abcde marked on your board. It's always been my understanding that the IMU, controller, and any peripheral hardware share a common ground. That is to include the ground on the input and output rails. As you can see from the photo I posted mine happened to blow the trace between the feeding the ground on the input rail
I actually found my old board that I blew the exact same way you did. But my trace was on the input rails. You can see where I soldered a jumper wire bridging the connection. I can't help but feel that there is a blown trace somewhere as well. It took me sometime to find it.
Looking at your 'c' photo, it only looks to me that the red coating has pulled off the board. What you see is a copper trace/plane, likely a ground.
I found an old pdf of the APM HERE. (older - no shield but APM). There might a be a slight variation due to 1.x rev.
You have two (2) problems:
We must fix #1 before we can evaluate #2.
Will be back with some more ideas...
-=Doug
I got the rar file unwound and whipped up a quick combo schematic. There are two fuses..
As your USB connection is working, the Shield fuse must be good. The other fuse, on the APM might be suspect. Usually the power from a drone system wiring is provided to the output headers. This +V goes to a diode then a fuse (as in APM2.x) and finally is called Vcc. Notice that APM1 has a voltage regulator for larger inputs than +5VDC. Not so with APM2.x. Several builders are having trouble providing input voltage to specification for APM2.5 and experiencing assorted boot/function issues.
Good luck!
-=Doug
Hello Jon, I have done this as well with the APM1 and APM1.4. Do you have a eagle file or a way to follow the traces? I was able to repair mine by putting it under a scope and resoldering a burnt out trace. That has been some time though. Follow the voltage meter pinouts under a scope and see what you can find. What better way to learn more about your APM. It can be fixed though.