[Jonnycat26]

I just went a little over 1000 miles in my 3 week old 2004, so I just figured I'd post some observations and musings. I should note that of those 1000 miles, 200 were put on by service when my Prius died.

Positives:
* Passing power is much stronger than I had anticpated. I have no trouble passing people on the highways.
* The nav system has really proven itself to be quite a valuable option. I've found ways home from work that I just didn't know existed. Despite it's fondness for routing me thru gangland wherever possible, I've had no issues with it.
* I've just hit 430 miles on my last tank, with 2 bars left. The MFD says I'm averaging 49.4 MPG. Not bad at all.
* The stereo, while not a thumper, is pretty crisp. Turning up the bass a little helps.
* The bluetooth speakerphone functionality is great. The prius's understanding of the bluetooth protocol, as it relates to the address book (vCard) is somewhat braindead I think.

Negatives:
* Don't get near trucks on the expressway if you're moving over 65mph. Just don't. I'm not sure if it's the 15" tires, or the weight, or a combination of both, but you'll do a little unintended weaving. Maybe a tire upgrade would help.
* No auto door locking.

Overall, I'm pretty happy, with the exception of the car dying in traffic on me. Anyone else have anything to add?

 

[Knguyen]

Hi Jon,

can you elaborate more on the die part. Like what happen, what went wrong, what did the dealer say

 

[Jonnycat26]

Hi Jon,

can you elaborate more on the die part. Like what happen, what went wrong, what did the dealer say

According to the dealer, the inverter died. Which means that while I was driving, the engine cut out, and I was left with electric power only, which really can't maintain speed on a highway. Luckily nobody was around, and I got into a safe parking lot to wait for a tow.

It happened 3 days after I owned the car. Just outside the 72 hour return period allowed by law in NJ. If it had happened within it, I probably would have cancelled the deal because it was a hell of a thing to have happenl. But since then, no issues.

 

[Knguyen]

Hi Jon,

"The inverter die"? and the engine cut out?. That does not seem right. the inverter is use for controlling the electric motor/generator not for the ICU. Unless the part of the inverter that supply power ocnversion from 200VDC to 12VC to provide power for the 12V system.no..no... that's not right either unless the Prius engine does not have a 12VDC gerenator to recharge the 12VDC. The Prius have a delicated generator so it can recharge the battery and provide power to the traction motor at the same time. I believe then an inverter or switched supply circuitry convert the 200VDC from the generator down to 12VDC to recharge the 12DVC battery. OK.. OK.. may be a low power inverter that supply the 12VDC for the 12VDC battery die and leave the 12VDC battery high and dry. Did the LCD and other normal instrumentation still alive at the time you try to pull it off the road? or did everything when blank except for the traction motor...? But that mean the drive by wire system must also die unless it have it own supply from the traction battery too. Hmmm I wonder... but that good that every thing is ok now.

 

[socaldriver]

My car also cut out on the freeway. To say the least, running on electric power only doesn't work too well on an LA freeway. Anyway, I took it to a dealer that, luckily for me, was located at the very next exit. I arrived half an hour before the service department was set to close. The service tech on duty had not been trained on the '04 Prius. He wasn't sure what caused the problem but expressed his opinion that the car was ok to drive back to my regular dealer. This is exactly what I did and am waiting to hear the results.

Can anybody explain the previous post to me in laymen's terms? I would like to know what caused this problem.

 

[Jonnycat26]

Basically, when my car died the MFD was still functional, and all of the warning lights came on. The engine wouldn't stay on. I have the codes if anyone wants them, and what it boiled down to was DC to DC inverter failure. I have no idea what was going on there.

When I pulled over and tried to restart it, the car would not go into ready mode, and all of the lights stayed lit. The MFD still worked, and very helpfully said "Problem". Indeed, it was a Problem.

That was 2 weeks ago today. So far the car hasn't had an issue again. I'm still a little nervous, and it will be some time before I "trust" the car fully again, but that's how things go .

socaldriver, how far was your regular dealer from the dealer who recommended you drive it there? Personally, I would have insisted on a tow. If the engine won't work, you're really playing with fire by driving on just the battery alone.

 

[Knguyen]

Ok, I'll try it.

a normal ICU need standard 12VDC to run everything from the ICU electronic to ICU engine control system. A normal ICU have a 12 VDC generator to provide recharge power to the 12VDC battery and at the same time power everything that run off the 12VDC. If the 12VDC generator die. the car will able to continue to run until the 12VDC battery die. When that happen the ICU die.

So for the Prius ICU to die that mean the 12VDC battery AND what ever recharge the battery also die. if the 12VDC battery die then that mean it's have not been recharge, which mean the 12VDC charger circuit die. Now the Prius have 2 high voltage electric motors, that mean to charge the 12VDC, a step down or a switching circuit (a high effiency stepdown circuit that use regularly in labtop computer system). So if the circuit die the 12VDC battery EVENTUALLY dry up and die too.

BUT everything inside the car such as the instrumentation, the LCD, the CD, the interior light, the exterior light use 12VDC. So if the 12VDC battery die and the charger die, so is everything inside the car would also die. That mean you would not see the LCD, the instrumentation. and may be the drive by wire system too. It is kind of confuse unless you have the schematic of the 12VDC power system of the car then you can tell what connect to the 12VDC power supply and how the 12VDC power supply and the 12VDC battery got recharge. As I undestand it, the inverter is usually to step up the voltage, not stop down. So I was supprise that the dealer said that the ICU die because of the inverter.

That why I ask about the instrumentation and LCD and Fan and CD if they still alive or dead.

By the way the LCD is the latest generation of LCD. It's called transflextive LCD. expensive stuff. A laymen term would be sunlight readable LCD.

I hope it help..and... did your instrumentation went out ? or was it still a live.

 

[Knguyen]

Jony,

Now I understand a bit better DC to DC converter is not an inverter. Laymen term for a step up would be inverter. A DC to DC converter is use to change one voltage from on to another, in this case from 200VDC to 12VDC. But since the Prius is an advance tranportation machine with a lot of computerized system. It's can and did able to detect a DC to DC failure and shutdown the ICU. Because everything inside the car run of 12VDC it have only about couple of hours before the 12VDC battery dry and die. The Prius prevent the ICU to run to save 12VDC power and keep the computer "core" running to inform you what did happen and also provide power to the drive by wire system to keep you from lockup (I assume here because drive by wire is a sensitive computer stuff too and can't be power from a 200VDC battery).

As for the cause, heat would be a prime suspect, next would be water corrosion, then after that parts defect, manufacture defect and or tolerance stackup..

I hope it help

 

[socaldriver]

I do believe I experienced the same thing that you did. The ICE kicked in right before I pulled into the dealership so I was no longer running on battery power alone. The battery was severely drained at that point. My dealer is 50 miles away from where the breakdown occurred. Since the ICE was working and the battery was charging, the technician felt it would be safe to drive the car to my regular dealer.

 

[Jonnycat26]

I do believe I experienced the same thing that you did. The ICE kicked in right before I pulled into the dealership so I was no longer running on battery power alone. The battery was severely drained at that point. My dealer is 50 miles away from where the breakdown occurred. Since the ICE was working and the battery was charging, the technician felt it would be safe to drive the car to my regular dealer.

How far did you drive on battery alone? My dealer claimed I could go up to 15 miles, but that seems amazingly high.

 

[Knguyen]

Hi guy,

I read some where about a couple weeks ago that there was a guy who want to findout how far to drive on the battery. He unintentionally did it and suceeded. He claim that it only go to about 2.5 to 3 mile max. after the ICU die. At the end, the traction battery so drained that his car wouldn't shut down 3 or 4 time. If my memory is correct he just go some gas from a local and put it in and start it back up. There was no damage to his car. I am not sure if the traction battery can drain all the way with out any permanent effect. If I happend to see it again I post the link for you guy.

 

[ifftster]

2-3 miles is about how far i can go with ev engaged. there are a few factors such as a/c and speed though. fortunately at 2 bars the ice starts back up to charge the batteries.

 

[RSnyder]

The 2004 Prius has two DC-DC converters and two DC-AC inverters. So when Jonnycat26 says he was told that he had a DC to DC inverter failure, it could have been any one of the 4 devices, slightly incorrectly named.

Since he says he lost engine power, but was able to drive on battery power, I'm inclined to think he experianced a failure in the DC-AC inverter that controls MG1, the smaller of the two Motor/Generators which controls engine speed. If the other DC-AC inverter failed, then MG2 would not work. Since it's the motor that can directly provide power to the wheels without help from the engine, it almost certainly did not fail.
Likewise, the DC-DC converter that switches between the 500 Volts used by the DC-AC inverters and the 201.6 Volts used by the high voltage battery could not have failed or battery power would not have been available. The DC-DC converter that switches from the 201.6 Volts of the high voltage battery to the 12 Volts of the rest of the car probably did not fail because the 12 Volt battery would have kept the computers running as long as it could, then the whole car would have shut down.

Socaldriver might have experienced the same problem, but failure of either of the converters or inverters should be very rare. There are many things that could cause the computers to shut down the engine. Hopefully, there are codes stored in them that the service technicians can use to permanently fix the problem.

 

[Jonnycat26]

Socaldriver might have experienced the same problem, but failure of either of the converters or inverters should be very rare. There are many things that could cause the computers to shut down the engine. Hopefully, there are codes stored in them that the service technicians can use to permanently fix the problem.

My problem was fixed, and if you're interested, I can post the codes.

 

[Knguyen]

Hey wait a minute ....the 200V to 12V DC to DC could fail too and the car system on 12V could still be on because of the 12V battery still alive. but it would still on as long as the 12V battery .... oh well I am only try to do a logical deduction here without schematic and error code, it's a fishing in the dark with the ear for me. I'll shut up then....

 

[socaldriver]

It would be good to post those error codes. The dealer was unable to find anything wrong with the car.

 

[Jonnycat26]

It would be good to post those error codes. The dealer was unable to find anything wrong with the car.

Here's a list of the codes that the diagnostics found on the car...

C125 9 C1310 ABS Codes. P0A94 HV ECU SUB CODES INFO 1 545 INFO 2551 INFO 3589 INFO 4583 INFO 5 0.

That's the list they gave me, formatted as I got it.