Gen 2 Red Triangle of death

it could be. do you mean the engine is not turning on? what did the mechanic use to scan the codes? how are your mpg's?

 

"HV Battery Malfunction". Could be several things like HV battery control ECU, or even having run out of gas. The second "freeze frame data" narrows that down quite a bit.

This indicates a problem with the regenerative braking, and is triggered by the above code. A symptom rather than a cause.

I don't see that as a valid code for a GenII Prius.

"Low voltage error" comes with the failed 12V battery.

This can be ignored. (Light sensor on dash.)

"Interior Verification Abnormal". This says the car doesn't recognize the key fob inside the car. Which is odd.

I would say that this is quite inconclusive, and possibly an artifact of the 12V battery failure. As has often occurred here, when a generic Brand X reader is used to retrieve codes, there can be incorrect or spurious results. There could be additional information in other ECU's that are important, but the scanner does not query. I would say get another reading using Toyota Techstream software. If you want to do that yourself, get a mini VCI ($30) and an old laptop. Clear the codes and see if they return. Otherwise, get a scan from a Toyota shop, or someone that does use Techstream.

Did you ever run out of gas?
Do you hear the battery cooling fan running loudly by the back seat?
Does the State of Charge display fluctuate from green to purple and back frequently?

 

Maybe double check to make sure that your new 12v battery was properly charged before install?

 

You have C2318 Low Voltage Error (Power Supply Malfunction) and low voltage has caused random codes and problems to many other people.

So check it first. Check the 12V battery voltage. If its ok check that cables have good connections including the connection at the other end of ground cable. If those are ok disconnect the battery for (at least) 10min and see if it fixes it.

If your 12v battery is low try charging it and then disconnect the it for (at least) 10min and see if it fixes it. If it works but problems return you have problem with 12V charging system.

 

All very good advice above. Also the fact that you have an ABS/VSC/TRAC codes will inhibit regen. Check you have at least 12 volts with a voltmeter at the jump point in accessory mode.

John (Britprius)

 

C2318 does not show up in the brake control manual. Which ECU is it controlled by?

 

Shift control system (parking lock control)

 

Another good reason to suspect the 12 volt battery or supply cables.

John (Britprius)

 

For a new battery a voltage of 11.9- 12 volts is very low. It should be for a new battery at a minimum of 12.6 and as high as 13 volts.
The voltage when the car is made ready "14.1" is purely the charging voltage from the car, and in its self is of little value only showing that the car is charging at a reasonably high rate to try to recover the charge in the battery.
The HV battery cooling fan running at speed is not a good sign.

John (Britprius)