2018 jerking gallop slowed and died!

I'd guess fuel quality or fuel depletion before failed fuel pump.

If you have not already got a Prius-aware diagnostic scanner, I'd suggest picking one up if you want to do your own troubleshooting.

Not all trouble codes immediately manifest in a "check engine lamp" so you may find some benefit in scanning the car anyway.

The Autel AP200 and AP2500 are two inexpensive/DIY-grade scanners that are able to read every system on a 2018 Prius c.

Welcome and good luck!

 

how many miles on her?

 

When using OBDII adapters, you also need a phone or tablet with a program that converts the signal emitted by the adapter into visual error codes, digital data values, or graphs of the parameters being tested.

Sometimes there are compatibility issues between the phone and the adapter, and sometimes the adapter is incompatible with the hybrid equipment.

 

You may have a dying inverter coolant pump. Put the car into ready mode and check if the inverter coolant is moving in the reservoir. Alternative you can grab the pump to feel if its rotation or buzzing, while your waiting for your scanner.

Hope this helps....

 

Looks like you got some useful results there.

The scanner only works in an ultra basic mode until you cash in the "free subscription" thing, which you have appropriately done for Toyota vehicles.

With that unlocked, the tool is now doing deeper scans, and that P0AC0 code is your prize.

...and I gotta say, not a common one.

If the hybrid computer cannot accurately measure the current into or out of the hybrid battery, it's not going to be able to make good decisions and the car will drive weird if it drives at all.

I don't happen to know the next troubleshooting steps for that particular error. I have seen it mentioned in other threads relating to measurement errors- the sensor is not correctly communicating its results back to the computer. (not the only possibility though)

In this situation I would suggest that you consult the actual repair manual, which is available to us mere mortals via subscription from Toyota. I have rented it before and it is a great resource.

 

Is this a copy of the screen from AP200? For some reason it doesn't show the error subcode. It is also strange that the Frozen data of the P0AC0 error does not show important parameters of the high-voltage battery.

P0AC0 Code Hybrid Battery Pack Current Sensor 'A' Circuit Range/Performance was often encountered on Gen2 or Gen3.
Usually it was due to disconnection or incorrect connection of the current meter sensor contacts.

A battery current sensor is installed to the positive (+) cable side of the HV battery and detects current flowing from the HV battery. The battery current sensor outputs voltage, which changes between 0 and 5 V according to the detected amperage, to the IB terminal of the battery voltage sensor. The battery voltage sensor sends signals to the hybrid vehicle control ECU assembly. The hybrid vehicle control ECU assembly determines the charging and discharging amount of the HV battery based on the received signals and calculates the SOC of the HV battery through the accumulated amperage.
The operation scheme is simple.
The troubleshooting path is usually the following options: checking contacts, replacing the high-voltage battery ECU, replacing the current sensor.

Also T-SB-0166-09 came out on Gen2, where the problems were in the battery ECU.
https://priuschat.com/attachments/t-sb-0166-09-pdf.32383/

 

Why scroll through screens? Click the "Save" button and get the AUTEL report in a pdf file, which you can attach to the message in the topic. It's simple and clear.

https://attachments.priuschat.com/attachment-files/2024/08/254644_Attachment-1.pdf