Stall in San Fransisco

Hi Stalix,

Have you ever had the auxiliary 12 volt battery replaced ?

Lead-Acid batteries can develope intermitant shorts, and high resistance. If a cell shorts out, that may drop the voltage below what is needed for the Prius electronics. If it develops high resistance, the amount of current required may also just drop the voltage too low.

I hope its not the DC-to-DC converter.

If you have never replaced the 12 V battery after 6 years, that is the most likely thing that is bad. 12 V Lead Acid batteries rarely last that long.

 

Hi Stalix,

I am not a total expert on the Prius, but thought I would give you a quick response.

Not sure what happened when you swapped batteries. But if the terminals were not clean, this would cause similar problems.

When the car is started, the 12 volt batery closes the main-disconnect relay inside the drive (or hybrid) battery box. The purpose of the relay is to disconnect the drive battery from any external circuitry during power down, or in the case of an accident.

Once the relay is closed, drive battery current flows to the inverter, which routes it to the MG1 (called the generator sometimes), which then cranks the engine.

Electronic circuitry is typically designed to operate at specific voltages applied at various points of the circuit. If one of the voltages drops below the design value, the circuit might not work as designed. There are devices called "voltage regulators" that set the voltage. One part of the circuit might run at 5 volts - like logic circuits and a computer. Another might operate at 10 volts - like an analog circuit used to receive and precondition signals from sensors. If the voltage drops down below 12 volts, the 10 volt regulators will drop out of regulation, and the sensor signals be corupted. A loose connection might cause intermitant dropouts of the voltages, which would also corrupt the sensor signals. The supply used to light of the MFD panel might also need a minimum voltage for its power oscillator to switch, so that it can provide AC signals to voltage changing transformer.

This is all general stuff, and I do not have specific information on the Prius. Yes, a bad battery, or connection from the 12 v battery could cause problems you reported to the best of my knowledge. That does not mean that the 12 v battery and its connections are the cause, or the only defect. Running the car on jumper leads is NOT sufficient due to the intermitant connections that can occur as the jumper battery clips move around.

When you hit the brake, or otherwise use extra 12 volt power beyond what a damaged or weak battery can provide, (brake lights might drop the 12 volt supply voltage) it could then effect the electronic controls. With the result that they go offline, and the car just stop, or the computer react incorrectly.

What you typed seems to indicate the 12 V battery is not being charged though. Which may be a more serious problem. But probably not the computer or the hybrid battery. To avoid damage to those, you should get it to a qualified Prius mechanic soon. Do not run down the hybrid battery. If the engine quits, get it to the side of the road and call for help. Do not try to use the battery to run the car for more than a few hundred yards. And no distance at all if your in the pink State of Charge (SOC) bars.

 

<div class='quotetop'>QUOTE(donee @ Feb 11 2007, 06:51 PM) [snapback]388640[/snapback]</div>

I agree. Sounds to me like it's not recharging the battery. The friend's battery worked fine at first because it had a charge ... until operating the car drained it. I'd say take it to a qualified mechanic/dealership and let them sort it out.

 

<div class='quotetop'>QUOTE(Silver Phoenix @ Feb 13 2007, 11:58 AM) [snapback]389610[/snapback]</div>

You might also check to see if there's a main fuse for the 12v system that may be keeping the DC-DC converter or "alternator" from charging up the 12v battery.

 

Hi Stalix, unsure if problems with your 12 volt battery can cause all of that, but That ought to be a relatively easy system to diagnose. You need a Toyota shop, or if you can swing by Oakland, Art's Automotive.

You mentioned an earlier non-start trouble code (you may have meant P3190). I guess that the engine control module was not replaced at that time? This may be the source of your current woes. It would be warranteed until 80k miles (technical service bulletin EG011-03). However, there are other components in that TSB under 36k mile warranty which sometimes appear to need replacing as well.

If your shop finds the P1120 code, you may need a new accelerator pedal. Expense from Toyota; less if you buy one of my rebuilds. Accel pedal sensor problems do not always cause that code to be stored, but the feeling of losing power while driving is pretty diagnostic. Often called 'the big hand syndrome'.

Finally, there are cheaper alternatives to Toyota's 12 volt battery, if that turns out to be needed.

Please let us know your progress on this. Good luck.

 

Hi Stalix,

Well the dealer wont do it for free, but if all it is , is a cooling system buble, then a properly experienced Prius tech should be able to bleed out all the bubbles in no time, and little money. Galaxy, who's SO is a Prius Tech on the east coast has indicated it can be tricky to get the cooling loops right.

But, I would not drive it more than short, slow trips in cool weather till its fixed. You may want to change the oil too, if the engine got hotter than usual the oil maybe degraded. Mobil 1 full synthetic oil would be called for, until the overheating condtion is taken care of.

You want to get this taken care of fast. Both the engine and Hybrid Inverter have cooling circuits and seperate radiators. The Hybrid Inverter is expensive, and the older Prius are not so pletiful, so they may be short supply. If the inverter is not getting cooling, you will definately blow it.

If you do not know if the transmission oil has been changed, you should have it changed as well done too. Its due at 77K miles in a Gen 1 Prius.

 

Here is a link to a document that explains the NHW11 (2001-2003) Prius DTCs and subcodes:

http://www.ecrostech.com/Products/MiniScanner/UserManual.pdf

3125 related to inverter function and 3130, inverter cooling.

Excerpts from the technical manuals describing how to refill and bleed both coolant systems are in

http://autos.groups.yahoo.com/group/Prius_...olant%20change/

but I believe you have to join that Yahoo group (painless) to access them. If you have problems accessing these files PM me and I can email them to you directly.

Based on your new codes, I agree that the inverter etc. is having a heat problem but it is not necessarily "cooked". There is, apparently, a "limp-home" mode that allows the system to continue operating at reduced power levels when it is unhappy.

Bleeding the inverter coolant loop is a high priority. If your Sacramento mechanic still has questions on the procedure after reviewing the docs above, the independent hybrid shop in Oakland I mentioned earlier (Art's Automotive) may be a resource.

With the coolant loop functioning correctly, further driving should reveal if there is any damage. If you need a replacement inverter (and don't like Toyota's prices), they are removed from totaled Prius and sold by salvage vehicle dismantlers such as LKQ online (just one example). When they show up on ebay they are typically $300. Good luck.

 

<div class='quotetop'>QUOTE(Stalix @ Mar 12 2007, 10:08 PM) [snapback]404539[/snapback]</div>

There is an inverter coolant reservoir to the rear and left of the inverter. What color is the liquid and where is it relative to the 'fill line'?

When you turn on the car, do you hear a small pump run near the driver side, low? This is the inverter coolant pump that normally runs all the time.

BTW, salvage inverters are available and though I bought my extra one for $500, I suspect you can shop around and find one for less.

Bob Wilson

 

<div class='quotetop'>QUOTE(Stalix @ Mar 15 2007, 12:42 PM) [snapback]406156[/snapback]</div>

A failed pump could cause the problem. I don't have my maintenance manuals handy but maybe someone could walk you through the steps. There may even be a fuse to check.

Bob Wilson

 

Hi Stalix,

There is a good chance there has been no damage to the inverter. But there might be damage that would still allow the car to function.

In their writeup on the inverter developement, Toyota mentions the work they went through to put a temperature sensor right in the inverter switching transistor chip. This was unique for the time, due to the large electrical noise in such power devices, and the small temperature signal most temperatue sensative semiconductor devices deliver. The advantage to having the temperature sensor integrated on the chip is so there would be minimal time delay between an overheat condition, and sensing it. The sensor is also sensing the temperature of the very semiconductor (SiliconCarbide in the case of the Prius) that the inverter switching devices are operating through, not a metal block that the semiconductor may have lost thermal conductivity too. Sensing such a condition quickly and accuratly then allows the car to fault out, and avoid pushing the inverter chip too hot that it would fail.

But that does not mean that parts of the chip could become changed, and develop partial open, or higher resistance. Which would make the chip more prone to getting hot in the future. It may work just fine for average driving once the cooling buble is removed. And may not be damaged at all. Its just if you keep tempting fate by not getting it fixed, it will fail permanently eventually.

 

Just a note from a new owner(three days.) I saw in the warranty that salvage vehicles ARE covered under the CA emmissions control warranty, which may be still in effect for your car. The waranty is 15 years or 150,000 miles in CA on the parts listed for today's model. It includes the inverter and computers.That's how I read it anyway. Good luck.

 

i had this problem but not to your extent, my dash lights went dim , but luckily everytime i entered my driveway, i really hope no damage to your inverter/converter, if the car is not under warranty, change the inverter coolant, and check the water pump, i also have a feeling the pump that circulates inverter coolant may be damaged, need to get that checked too.

i am just hoping your inverter is ok, i ran my car in this condition and its still good as new ( considering i fixed the problem ), also make sure there are NO AIR POCKETS what so ever in the coolant, but using the toyota coolant its pretty hard to make a air pocket if you follow toyota instructions.

to check the pump, turn the ig on without ready mode, and pop the hood, facing the front of the vehicle there is a black pump located near the drivers side headlamp, this pump circulates inverter coolant, if it is possibly listen in that area, if you hear the gushing of water, if not , put your hand on it ( make sure the engine is cold too ) if iyou feel some sort of a vibration then it might be a good pump, also check the inverter coolant level, located right next to the inverter.


it is very easy to change inverter coolant, just drain and replace in the tank located next to the inverter, you must buy toyota long life coolant. hurry and do it before its too late.

for the sake of your prius i hope it gets cold

 

<div class='quotetop'>QUOTE(Stalix @ Feb 11 2007, 06:30 PM) [snapback]388579[/snapback]</div>

Does the car have a computer chip type thing in it? If so, it is very possible that it is no good.

I had the same thing happen to me years ago in a Plymouth Voyager.

It came to a dead stop.

It sounds like a connection problem or the computer chip is wacked out.