starts then dies

[b2kon]

Hello All!
I just bought a 2001 with 98K miles.
It was running fine, no probelms.
Because the trunk was so dirty, I decided to clean the trunk and removed the 12V battery.
When I re-installed it, the car would start then after 15 seconds or so, it would die. The red car with the exclamation point displays on the top right portion of the screen. It feels like it ran out of gas or something. The tank is still half full.
Then when the engine dies, the screen displays "PROBLEM" with three icons, ("PS", ???, "red car with exclamation point).
I tried making sure the grounding is okay...still the same.
I tried jump starting it thinking it might be a undercharged battery...still the same.
I tried putting it right away on DRIVE...the car moves..but after 15 seconds or so, it dies.
I tried the above methods from what I read on the internet searching for a solution to this problem.
Many thanks.
Tony

[Patrick Wong]

Hi Tony,

A few questions for your consideration:

• How many miles did you log on the car before deciding to clean the trunk?
• How did you clean the trunk - was water or other fluids involved?
• Have you securely tightened the battery connections?
• Do you have a digital voltmeter; if so, what voltage does the 12V auxiliary battery produce?
• Do you have access to an OBD-II code reader?

[b2kon]

Hello Patrick,

• How many miles did you log on the car before deciding to clean the trunk? I just bought the car a few days ago...i guess it was a long, long time since the trunk was cleaned, if ever.
• How did you clean the trunk - was water or other fluids involved? I used some water to clean it (no hose...just a wet rag) and I did not touch the battery pack or the electricals.
• Have you securely tightened the battery connections? Yes I did.
• Do you have a digital voltmeter; if so, what voltage does the 12V auxiliary battery produce? I don't have a voltmeter. What should be the voltage? I was thinking of getting a new battery tomorrow to see if it was the battery.
• Do you have access to an OBD-II code reader? Unfortunately, no.

Thanks Patrick!

- Tony

__________________

[ChapmanF]

Purely a piece of completely uninformed and tired wild guessing (from someone who just this moment walked in the door from the first 500 mi road trip in the Prius) - would it be possible that in the process of cleaning the trunk the *skinny* wire that attaches to the aux battery positive terminal fuse block got disturbed? The skinny wire attaches via a small two-pole plug (the other pole isn't used) and is also fused (of the two fuses in that block it's the small one, not the 120 A one).

The skinny wire is used for voltage sensing to regulate the converter output. A problem there might cause the system to go into READY and then after N seconds say "hey, I can't see my intended charging voltage, something must be wrong."

Again, I'm mostly grasping at straws - getting hold of an OBD-II scanner would be the more promising way forward.

-Chap

[Patrick Wong]

Originally Posted by b2kon

• Do you have a digital voltmeter; if so, what voltage does the 12V auxiliary battery produce? I don't have a voltmeter. What should be the voltage? I was thinking of getting a new battery tomorrow to see if it was the battery.

Hi Tony,

When the car is IG-OFF, the battery should be at 12.6V or better. A marginal battery can cause weird electrical problems, so it would be great if you could replace it.

If it turns out that this is not the problem, then you'll need to buy an OBD-II code reader to get some clues about the nature of your problem - or else have your car towed to the local Toyota dealer. Note that some generic code readers may be confused when plugged into Prius due to the multiple ECUs that potentially can produce trouble codes.

[ChapmanF]

Originally Posted by ChapmanF

The skinny wire is used for voltage sensing to regulate the converter output. A problem there might cause the system to go into READY and then after N seconds say "hey, I can't see my intended charging voltage, something must be wrong."

Well, I liked my theory, but I tested it this morning ... I disconnected the sense wire at the aux battery terminal and started the car ... ran just fine, no warning light, no code that my generic OBD-II scanner could see.

Then I kind of wanted to see whether my generic scanner would even be able to pick up a HV diagnostic code if there were one, so I looked through the DTC pages in the manual looking for some easy way to cause a code, and I did succeed in getting a triangle-exclamation-point and car-exclamation-point, but my scanner was still not able to read the code. Nuts.

I know it takes something like a Toyota scanner or a Graham scanner to read the specialized HV parameters, but is it the same way with reading the DTCs? Can anybody recommend a generic scanner that IS able to read DTCs from the HV ECU?

-Chap

[b2kon]

Hello Chap,
I checked that tiny wire that you mentioned and it is connected properly.
I was trying to get a new battery at Costco but they don't have it.
Can I try any other battery from my other cars (just for testing)?
Thanks.

-Tony

[Patrick Wong]

Originally Posted by b2kon

...
I was trying to get a new battery at Costco but they don't have it.
Can I try any other battery from my other cars (just for testing)?

Hi Tony,

You will probably find that the terminals from a regular 12V battery are too large to fit the Prius battery connectors. However if you can figure out how to connect the battery, you can use it for testing purposes.

Originally Posted by ChapmanF

Well, I liked my theory, but I tested it this morning ... I disconnected the sense wire at the aux battery terminal and started the car ... ran just fine, no warning light, no code that my generic OBD-II scanner could see.

Then I kind of wanted to see whether my generic scanner would even be able to pick up a HV diagnostic code if there were one, so I looked through the DTC pages in the manual looking for some easy way to cause a code, and I did succeed in getting a triangle-exclamation-point and car-exclamation-point, but my scanner was still not able to read the code. Nuts.

I know it takes something like a Toyota scanner or a Graham scanner to read the specialized HV parameters, but is it the same way with reading the DTCs? Can anybody recommend a generic scanner that IS able to read DTCs from the HV ECU?

Hi Chap,

What would be interesting is if you could hook up a digital voltmeter across the battery to read the voltage produced by the DC to DC converter when the Prius is READY; then disconnect the sense wire and see how much the voltage changes.

Regarding the generic scanner, my OBD-II scanner was successful in picking up a DTC produced by the traction battery ECU, but theres no guarantee that it would work under other scenarios. I owned the Ecrostech (Graham) scanner when I still had my 2001, and highly recommend that if you can locate and buy a used one.

I'm wondering what you did to produce a DTC.

If you want to produce a DTC from the engine ECU, you could disconnect one of the spark igniter connectors or the mass air flow sensor.

If you want to produce a DTC from the traction battery ECU, you could remove the orange interlock switch on the driver's side of the battery.

[hobbit]

Remember that "runs, then dies" could be a no-start condition
from the git-go, i.e. it wasn't running at all but simply being
cranked for those few seconds after which the HV ECU gave up.
.
Check the 12V, check that something didn't get dislodged in the
cleaning process like a harness connection, and have a look down
the throttle body. Pull codes if possible, although the ones
of P3190/P3191 class meaning "engine does not start" may not
be amazingly useful. Without more in-depth info it would be hard
to do much more in terms of diagnosis over the net...
.
_H*

[b2kon]

Thanks to all.
I will try and get the codes somehow and will keep you posted.

- Tony