1- You need to put the Multi-meter in diode Check mode. (should be a symbole similar to this one)
2- Check if you get a beeping song when touching de lead together. (or if you don’t hear any sound check if the multi-meter show 0000 or something similar)
3- Use the c25 capacitor to see if the 5v is short to the ground (it is the easiest part to access for checking the 5v to the gnd)
4- If you the doesn’t get the same result as touching the lead together, GOOD New the 5v is ok, but the problem is somewhere else. But if you get a beeping sound or the result is the same as touching the lead together, then you have a short over the 5v, and from my experience, it is 90% chance of a internal short over the can tranceiver (u401).