Battery dilemma

How far did you get before the engine died? The traction battery should have recharged the 12 volt in a pretty short time. I suspect the battery in the 06, probably the original was done for and this would not happen with a good 12volt battery.

 

There is a problem with the charging system. The car can run quite some distance with a defective inverter, as the 12V battery can operate the computers. But without the inverter transferring power from the high voltage traction battery to the 12V battery, the 12V battery will discharge to the point that the computers don't work.

I suspect that the inverter coolant pump has failed. Without cooling, the inverter overheats and drops out. If it overheats too much, then it's totally destroyed, but we don't know if that's happened yet.

Don't drive the car over 2-3 miles at a time until you can get the pump checked. If the inverter is still functional, it will charge the 12V battery until it gets too hot, and then drop out. Short trips will work ok, but longer trips will draw down the 12V battery to the point that the auto-start function will no longer function.

 

gene, if the 12V battery were merely drained, after a jump start you would have been able to drive it normally to the dealer. Something else/worse is wrong, and the only good way to get it to a dealer would have been to tow it.

 

Or maybe it is just as simple as the 12 volt battery is toast, and the new one is fine and it will never happen again. I believe there is a 10 minute shutoff on the interior lights, so you may only think it discharged the battery. The battery could have reached the end of its life and the light just pushed it over the edge. If you don't have issues in the next few days, you are probably just fine.

 

IMO, the Prius should be able to diagnose such a major failure of an important part (like the overheated converter) and display an appropriate msg on the display.

Come to think of it .. does the car display any diagnostic messages (in plain English) on the display (the same one that greets me so nicely with a Welcome when I start the car)? That would be a good application of the display.

 

You're kidding, right?
$135 for a Prius battery? Does that include labor at Toyota?
Did you DIY?

I called around and found $185 to be the best price to replace the 12V battery of my
2005 Prius. Nothing was wrong, but I figured that it was about time. I never let
battery interrupt my trips. They always die at the most inconvenient times.

 

A functioning inverter provides about 14V the entire time that a Prius is in Ready mode. A dead battery would not normally shut down the car like reported here. You would expect the normal starting and stopping of the engine to continue even with the 12V battery dead. I suppose a shorted battery might be enough of a drain that the inverter couldn't keep up, but that seems very unlikely.

There was a long, involved story about a pump failure that I can't locate just now. The pump failed, which allowed the inverter to overheat after quite some time. It was something like 10 miles of travel. When the inverter overheated, it dropped out, leaving the 12V battery to run everything. That was good enough to go another 5 miles or so. The result was that 15 mile trips worked fine, but add a few more miles and the 12V battery went flat. In this case, the P0A93 code didn't show up, even though it would be expected. Given the cold weather this time of year, a similar failure might go totally undetected with short trips and a brand new battery.

The inverter coolant pump was upgraded late in the 2006 model year. And the 2010 has an improved pump control system that should improve the life of the pump.

You can check if the pump is functioning ok by taking the cap off the inverter reservoir and seeing if the coolant is moving. Play the video at the end of the blog post at Luscious Garage | Blog | Prius Code P0A93: Inverter Water Pump Failure

See also the tread http://priuschat.com/forums/gen-ii-...g/36513-inverter-coolant-pump-takes-dive.html

 

Gene, are the displayed voltages within spec on the 12v? If not, I'd return it to the dealer under warranty.

 

I wonder if the 12v battery was completely shot. When he stopped the car, the gas engine shuts off. The 12v simply didn't provide enough spark to get the engine re-going. I guess the question is, is there anyway for us to keep the gas engine on?

 

The traction battery provides the power (via the inverter) when the engine is stopped so the 12V battery is not really required at all once the system is started.

There is no need to keep the gas engine going.

kevin

 

The only way this becomes an issue is if the 12V battery is shorting the 12V bus. It's very uncommon, but a shorted battery would drag down the 12V bus and cause any number of weird problems.

Tom

 

As I recall, one can see the voltage of the 12-volt system using the "hidden" menu.

 

Quick test to do:

1. boost and start the car in READY mode
2. disconnect the 12V battery, (-) side
3a. if the car quits READY mode ("dies"), the problem is at the inverter, not simply at the battery
3b. if the car continues to run, it may simply be the 12V battery

Can someone confirm the logic? Usefulness of this test?

 

first off, what kind of car do you have?

in a Pri, the engine does not die. it does cycle on and off depending on the state of the car. but after the car is started, it does not use the 12 volt battery, so having a dead one is not likely to cause your car to not run after its started.

if this is true, it sounds like you have a major traction battery failure along with several monitoring systems since your dash should have lit up like the tree on the lawn at the Kennedy Center