2016 500e Dead HV Battery

With the key turned one click, a Konnwei will normally connect AlfaOBD to the BPCM like this (click to enlarge):

Then read the status:

& scroll down to show the two critical numbers in the blue box I added:

Since I was on my phone at the time, I should likely add a few more things about post #3:

Electric Tire Shredder said:

1. Left the humidity sensor unplugged
2. Left the 12V and HV disconnected for 30+ hours
3. Checked HV fuse continuity
4. Made sure to reconnect HV per pics 3 to 6 of the sequence
5. Checked for 12+ volts at the wires (in case of bad connection) or on OBD
6. Cleared all faults in all modules incl. BPCM, OBCM, EVCM, PIM, etc.
7. If still no clunk, reset contactors.

Click to expand...

1. If the humidity sensor isn't just right of the rearview mirror, because the glass was replaced, you usually have to dig it out of the headliner. Pull perpendicular from the glass with each middle finger in the openings. Hold a round toothpick parallel to the glass & press straight into the crack to wedge the black socket away from the purple plug so you can yank it out. Leave it unplugged but you can tuck it in & hook the cover back on the left & snap up on the right:

2. Preferably disconnect the 12V first & insert a piece of plastic or cardboard to prevent sparking it awake. It's fine to just do the negative, & leave the positive connected. Preferably reconnect 12V after reconnecting HV.

3. The HV fuse should test out like this:

4. Here's the HV disconnect/reconnect sequence:

Click to enlarge, or scroll down for full-size pic since it's equally easy to get wrong or right.

6. As @fiatatat mentioned, note the faults before clearing, preferably selecting each one, to show their descriptions. Ideally get an OBDLink SX cable (or LX Bluetooth) so you can use the yellow adapter that's required to check modules such as the Body Computer.

7. Here's the contactor reset sequence:

With the key turned one click, a Konnwei will normally connect AlfaOBD to the BPCM like this (full-size pics in post #6 above):

Then read the status:

& scroll down to show the two critical numbers in the blue box I added:

...but I still recommend getting an OBDLink SX cable or LX Bluetooth in order to check & clear codes in the Body Computer & other modules that you can only access with a yellow adapter.

In the mean time, yes, step 5 above is to confirm that there's at least 12 volts in the system, because even a brand new battery can be drained pretty quickly, especially when there are error codes, & the contactors won't activate if it's just a bit too low. Sorry I don't know the exact number for your 2016 with its power-draining center screen, but someone reported that 11.9V was insufficient. It should show in OBD when you scroll down the BPCM data to see the top line here:

& please try to give us the HV pack's min voltage, so we can give a better guess about needing to drop the pack & charge cells individually. This shot is at 0.0000% (ran in neutral til it shut itself off):