Replaced fuse box housing - transmission "P" lock mechanism appears

Brought a rebuilt 2007 Prius and have been driving it for about a month while replacing a few parts.

The fuse box housing was cracked from previous hood damage, so I picked up a replacement fuse box from a junkyard. I did not swap the actual fuse box electronics or connectors, only the plastic housing.

The process was simple. I unclipped all connectors from the damaged housing, slid everything out, and snapped it into the replacement housing. Everything went back exactly where it was.

After finishing, I reconnected both the 12V and hybrid battery.

The car powers up fine, but now I get a red triangle warning and a message on the display saying there is a problem with the transmission "P" lock mechanism.

Here’s the strange part. There is no check engine light and no trouble codes showing. The car shifts into Drive, Reverse, and Park normally and drives perfectly fine.

I have checked all fuses and everything looks good.

Has anyone run into this before or have any idea what could cause a "P" lock warning when everything seems to function normally?

Thanks in advance.

 

I plugged in Techstream and here’s what I found so far.

The initial codes were B1210 and B1271, which appear to be related to the Gateway. From what I understand (and what AI suggested), these don’t directly cause the “P” warning but may indicate the ECU isn’t fully satisfied with system conditions.

I then checked the Hybrid Control system and found code P0A0D (High Voltage System Interlock Circuit High). I’m not entirely sure how to interpret that yet, especially since the car still drives fine in both Drive and Reverse.

One thing I did notice while testing: a few times when I shut the car down and restarted it, all the warning lights came on and the car would not go into Drive or Reverse. After shutting it down again and waiting a bit, it would start normally and drive, but the “P” warning still shows.

Still scratching my head on this one. Any thoughts would be appreciated.