the great jumper wire mystery

Sounds like something failed and was bypassed.

 

Those trouble codes are about the motor that moves the transaxle in and out of Park.

There are plenty of threads here about a sort-of-common situation where a power connection in that circuit, inside the fuse box, gets flaky, and an external jumper is added as a pragmatic way to solve it without opening up the whole fuse box.

My recollection, for what it's worth, is that that was more common in gen 2; if you search for those threads you might find more of them in the gen 2 forum sections. I'm not sure I've heard of it in a gen 3 or v yet.

Maybe it just had to wait for gen 3s to start reaching the same ages.

Or maybe the jumper wire was put there by someone who was thinking of gen 2.

 

If you are going to keep the fuse tap in place, at least do it right. Use one of these to create a new fused circuit for that wire.



SM-G781V ?

 

what happens when you pull that wire and cap it with a wire electrical tape and or wire nut?
gotta love homemade remodeling.

 

A search for Prius "P Lock Malfunction" here and on YouTube should lead you to information about some of those jumper wire fixes.

As ChapmanF mentioned, the posted jumper wire solutions seem to focus on Gen 2 models.

My car is a Gen 3 (2014) and I too experienced a similar issue about three years ago. I recall getting a C2310 code which is slightly different from the codes you reported. The C2310 "open or short" is related to continuous 12 Volt power supplied to the transmission ECU. I believe it provides continuous power to the ECU RAM so that it remembers the "Park" pawl position while the car is powered off. The problem was intermittent, exhibiting various odd behaviors and the triangle of death. At times the car would not shut down properly.

As your codes are different, it should be mentioned that some of the 12 Volt power to the ECU is switched (different wire/contact) and you may need to look for an upstream or downstream issue. Some careful study of the service documents should help.

I was unable to find any damaged wires, blown fuses or corrosion on any easily accessible connectors. The local Toyota dealership was unable to zero in on the issue either. The second trip to the dealership resulted in a quote for about $6,200. That was for a new wiring harness with a part price around $3,500 and 18 hours of labor to pull the dashboard and install the new harness. What could possibly go wrong with that? At that point I decided to take matters into my own hands. I ended up running a new power circuit from the inside fuse box above the driver's feet to the transmission ECU in the controller village behind the glove compartment. The original circuit had provided power from the fuse box under the hood. Haven't had a single problem since making that modification.

These "P Lock Malfunction" problems have the potential to drive you crazy. With some determination and study you should be able to sort it out. Good luck.