Was that arcing and melted off? How did it happen--curious minds wanna know...
Sure looks like it to me.
Here's the rundown. I bought the car new in 2016. It's the 24kWh, and only has about 35k miles. I was driving and it lost power and shifted into neutral. It would not go into ready mode. I had it towed th 2 miles back to my house where I began troubleshooting. Reading the DTCs pointed me to P311C, which has diagnostic steps that look for shorts in the high voltage components. When I got to the step of checking the motor inverter, I saw charring on the terminal (red). I didn't notice what was missing until later. (blue)
So I decided to pull the PDM since there was obviously some heat coming from the inverter. (followed this video, it's a great one -
)
When I got to the part where you remove the bolts that hold the PDM to the inverter, I couldn't find them. There are supposed to be 6 bolts connecting the inverter to the PDM, and there were none. The only solid attachment of the PDM was the bus terminals. After having disconnected the coolant hoses, brackets, and getting the charging cables off their mounting points, the PDM was wobbly as hell and clearly not bolted down. Over time, the wobbly PDM vibrations seem to have caused one of the copper terminal connectors on the inverter to crack, overheat, arc, and finally disconnect completely.
Looking at the underside of those tabs on the inverter, there are no marks at all from fasteners, indicating that the bolts were never installed in the factory.
Parts for the inverter aren't available. A new inverter from the dealer is around $4k. A used one is probably $500-$1k.
I've opened a case with Nissan and I'm expecting a call tomorrow from an agent. In the meantime, I thought maybe someone had replaced a faulty inverter and maybe had the old one laying around. It's a shame a $4k inverter was ruined for a lack of $8 worth of bolts the factory missed.
