[Rooster420]

Hello everyone this is my first post here and am grateful for any help I may receive. My wife was driving our 2005 prius and about 200yds from the driveway it just stopped running. We pushed it back home and started tinkering when we noticed that the 12v battery was low. The car would not power up all the way. The dash lite up like the 4th of July but would not get "ready". We pushed it home and I disconnected and charged the 12v battery. After reconnecting the battery the car would now become ready but only drive a short distance on the electric motor and the gas motor won't turn over at all. That's were I am at now. Oh and the display screen has a big message on top that just says problem.
So it will drive on the electric but the gas engine does nothing. Any ideas? Thanks again.

 

[Phoenix]

The ICE (Internal Combustion Engine) is controlled by the hybrid system. When the computer sends a START/RUN command, a sensor checks to verify that the ICE is running after a short delay (less than a second). If the ICE is not running, a FAILED-TO-START error code is recorded, and the hybrid computer will not issue further START/RUN commands.

The symptoms may appear as if the ICE stumbled/stalled, or the ICE may just not start at all. However, the error code will appear when a scan meter retrieves any error codes that exist.

You can reset the system by disconnecting the 12-volt battery for several minutes, and then reconnecting it. This may allow the ICE to start and run. However, the original defect that caused the FAILED-TO-START error may still exist.

You should start by checking the obvious:

Is there fuel in the fuel tank?

Is the 12-volt battery defective (discharged or worn out/won't hold a charge)?

Have you recently had periodic maintenance performed? Specifically, have you had the ICE engine oil and filter changed?

Note: Overfilling the crankcase will allow motor oil to be sucked into the ICE, which will contaminate the mass airflow sensor and cause the engine to stumble when the START/RUN command is issued. The crankcase holds exactly 3.7 quarts of oil. If you (or the Toyota dealer's service department) added 4 quarts, this may cause a FAILED-TO-START error. This has happened twice with our Prius; and both oil changes were performed by the same Toyota dealer where we purchased our car, new, in 2002.

There are other hybrid system and ICE problems that may cause these symptoms, but you need to obtain the fail codes to troubleshoot the problem. Most auto parts stores (AutoZone, O'Rielly's, and similar) will read the codes for you for free (or loan you the meter to read them yourself); or you can purchase one (they are not too expensive). If you get the codes and post them on this thread, PriusOnline members can help you determine the most probable cause for your problems.

Finally, your best (and most expensive) option is to take your Prius to a Toyota dealer. They most likely will charge to troubleshoot the problem, but they will usually apply troubleshooting fees as a credit towards any repairs that they perform. And, you will probably have to have the repairs done by them, anyway; because most hybrid system and ICE parts are only available from a Toyota dealer.

Note: I strongly suggest that you do NOT go to an independent garage/repair shop; as there are very few whose technicians trained to work on hybrid vehicles.

 

[Rooster420]

Thanks for the help. I did disconnect the 12v battery over night and it did the same thing. The ICE never even tried to start. I am going to call autozone and see about borrowing a code reader since I dont think I can drive the car to them on just the electric motor.
Any idea what the "problem" warning on the display screen would be about? It also has the usual warning lights going up by the speedo. Thanks again and I will keep ya posted.

 

[Phoenix]

Without the error codes, any troubleshooting advice is purely guesswork. However, here are a couple of failure modes to think about:

If the READY indicator does not come on. It could be the traction (high-voltage) battery. Short of a collision, this is about the worse thing that could happen. Last summer, the traction battery failed on our 2002 Prius; and the replacement would have cost us $3,200-$3,600 (from the Toyota dealer). However, Toyota and our dealer absorbed part of the cost as a goodwill gesture for us buying 3 Toyotas from them; and our out-of-pocket expense was only $850 (which is still a lot of money).

Another common failed part is the hybrid coolant pump. It's powered by an electric motor; and when the motor fails, the pump stops and the hybrid electronics overheat. This also causes similar failure symptoms. However, after everything cools down overnight, the READY indicator will usually reappear; and the ICE will start, but for just a short period. Over the years, this part has failed twice on our Prius. Parts and labor to replace this pump is around $350-$500, if my memory is correct.

And, the overfilled oil crankcase... Over the years, this has happened twice on our Prius; but both times were when first starting the vehicle in very cold weather. After oil changes, I now check the oil level before leaving the dealer's service department; and I have had them remove oil on several occasions. While this is a possible cause, the symptoms don't quite match up; and it's not the most likely cause. However, it is the cheapest to fix.

You have not stated how many miles your Prius has on the odometer, nor if any maintenance or repairs were done recently (in the last few days or weeks). This info might provide some insight on what might be wrong.

I perform preventative maintenance and minor repairs on our other vehicles. However, the hybrid systems in a Prius (even our 2002) are much more complex than regular cars. Consequently, even though I have some mechanical experience, all repairs on our Prius have been performed by the dealer.

If you need this vehicle immediately, I suggest you have it towed to your dealer for troubleshooting and repair. From experience, you may ultimately be unable to determine exactly what has failed; and your Prius is probably going to end up at the dealer anyway. Besides, you will most likely have to purchase any hybrid system or ICE repair parts from them; because these are not available from most auto parts stores.

In 12 years of ownership, our 2002 Prius has only had about $1,600 in actual repairs (traction battery and two hybrid coolant pumps), which is exceptional for any vehicle. So, despite the inconvenience and immediate expense, the repairs you now face may not be as bad as you think (or they could be) when considered in perspective.

Note: This estimate does NOT include fuel, tires, shocks and struts, and routine/preventative maintenance.

 

[Rooster420]

Thanks for the input. The car has 185k on it. Has had regular oil changes and thats it. Never had to have any problems fixed. The ready light does come on and the car will move on the electric power only. The 12v battery was dead and there is a chance that the car was left powered up for over 24 hours after my wife drove it. I disconnected the battery and charged it to no avail. Will be getting a code reader from autozone saturday to reset the codes. Will let you guys know how it goes. Fingers crossed. Thanks again for all the help. This is a great community.

 

[Phoenix]

Have you performed load test on the 12-volt battery? After you charged the battery, will it hold a charge; or does it slowly drain on it's own down to 10.5-11.5 volts, which usually indicates a cell that is shorted internally.

You can run an in-car battery test, which will indicate the charge level. See instructions at this link: http://www.elearnaid.com/prhadonotstr.html

If you need a new 12-volt battery, eLearnAid sells Optima Yellow Top batteries that will fit in a Prius. Shipping is quick and free (at least, when I ordered one last fall).

Note: I have no affiliation with eLearnAid other than being a satisfied customer who has purchased three batteries from them (two for our 2002 Prius and one for our 2008 Tundra).

 

[Rooster420]

Ok so I finally got a code reader from autozone today. There were 5 codes. Here they are. Any help is always appreciated.
1. POA1D hybrid power train control mod confirmed
2. POA4C generator position sensor circuit range/performance confirmed
3. POA4D generator position sensor circuit low confirmed
4. POA4C generator position sensor circuit range/performance Pending
5. POA4D generator position sensor circuit low Pending

I wrote down the codes then hit the erase button on the reader and it only erased to first code. Now the car won't go back to "ready" and move on electric anymore. I disconnected the battery again and am going to reconnect and see if it helps with the ready issue again. Thanks again everyone.

 

[Phoenix]

These fail codes indicate the following:

P0A1D: Hybrid Powertrain Control Module — Test and replace (if necessary) Power Management Control ECU

P0A4C & P0S4D: Generator Position Sensor Circuit — Test and replace (if necessary) one or more of the following:

• Associated Connectors and Voltages

• Associated Wiring Harness(es)

• Transaxle Assembly

It appears that most who encountered these fail codes ended up at the dealer and likely incurred expensive repairs.

Just my opinion: If this were my Prius, I would take the car to the Toyota dealer’s service department and have them troubleshoot this problem WITHOUT performing repairs. Then, you can decide how to proceed; i.e., whether to have them fix your car, or whether it’s time to go new/used car shopping.

FYI, most dealers charge one hour minimum (it may take longer), and the current hourly rate is over $130. However, most will credit troubleshooting charges directly to the repair bill, if you have them perform the repairs. If you decide not to fix your car, take it home and do the repairs yourself, or take it to another shop, undoubtedly the dealer will charge you for troubleshooting time.

If you have a good relationship with your dealer (usually, this means you have had them do all preventative maintenance and repairs), I’d ask them if they can absorb part of the repair costs. As previously stated, last summer we had the traction battery in our 2002 Prius replaced for about $850 (normal price for parts and labor is $3,200 to $3,600) after reminding our service department manager that we had purchased three Toyotas from them, and had them all serviced there.

Sorry for the bad news… After this problem is resolved, please post the failure cause, corrective action and cost (if vehicle is repaired).

Good luck!

 

[Rooster420]

Thanks for the input Phoenix. Was doing a little wishful thinking and hoping since the car will go into drive and reverse and drive around the block on the electric motor that the trans is ok. Any thoughts on this? I did go connect the battery back up and it now drives around again but still no ice. Tomorrow when I take the code reader back I will take the 12v battery to get tested.

 

[Phoenix]

Unfortunately, the Prius systems are so complex that failures that involve just about anything under the hood have to be troubleshot and repaired by the dealer.

Not sure if I mentioned this, but until I purchased our 2002 Prius and 2008 Tundra, I performed most minor repairs (short of pulling the heads off of an engine) on all of the vehicles I've owned. However, anything under the hood of a newer Toyota is beyond the normal shade-tree mechanic. Fortunately, Toyotas are very reliable... until they quit running.

When the traction battery in our Prius failed, I was so frustrated that I was about ready to trade it in on a new Camry or Prius hybrid. However, after recalling that I had spent less than $1,000 on repairs in 12 years and 135,000 miles of ownership, it was easier to swallow the $850 estimated repair bill.

I think testing the 12v battery is a good idea. However, beyond that, until you find out exactly what's wrong with your Prius, we're just shooting in the dark.

It's always possible that it is a defective sensor or cable; but with 185,000 miles on the odometer, I'd start saving your money, whether it's for repairs or a down payment on a new or newer car.

I've got my fingers crossed for you...

 

[Rooster420]

Ok sorry for not posting in so long. I was low on cash so the car had to sit until I could afford to tow it to the dealer. The problem has been fixed and it only cost me $220 plus $60 for the tow. The problem was mouse eaten wiring to the transaxle. They fixed the wires and the car is back to normal. Cost $100 to diagnose and 120 to fix the wires. Soooo glad it was simple. Thanks for all the input this is a cool site. If anymore problems arise I am sure I will be back. Thanks again, Rooster

 

[Phoenix]

Great news! Glad to hear it was something simple and relatively inexpensive.

Happy trails!

 

[Don Tait]

Not so easy

I have the same problem except the car was hit in the rear (broke bumper and slight dent) since then the ICE has never run. Moves on battery, no ICE
PS I have red triangle of death and error code C1259 But still able to get ready once in a while then spin wheels (for a min. or drive 30 feet.)
Slowly the main battery will die without the ICE so fixing that first is what I need to do. Thanks guys.
No dealer for about 150 miles so a trouble shooting guide would be great.
Don.

 

[juanillo]

i got a 2008 prius. came the hv battery dead,i get a rebuilt battery and the gas engine wont star because i notice the gas engine was frozen. i replace the engine with a use one 70 k miles. but still wont star and not shifting to D or R only P to N. codes i have c0200,c0205,c1259,c1310. i need help

 

[MarOmega]

If anyone has photos of the wiring connectors for the Generator Position Sensor, and where it is located on the ICE, that would be a great help.

After using the diagnostic reader, (we found a really cool OBD that connects to Android or iPhone for $8 on Amazon) we got the following codes:

P0A4C Generator Position Sensor Range/Performance
P0A4D Generator Position Sensor Circuit Low

Since it did not end in A or B, I am not going to sweat the thought of tearing out the trans axl and try to replace the position sensor. This sounds more like a wiring harness issue. My assumption is the connector itself may be chewed up, or broken (hopefully just slightly loose)

First thing we did is change out the 12v battery as every Prius forum suggests is the root of every single Prius problem. Thankfully, AutoZone accepted the battery's return and refunded me the $261 that it would have cost for this mistake.

Since the car is 20 miles away from me right now, I cannot look for myself, and I am not sure where to look. I have a ton of errands to run first, so I am hoping someone will drop some pictures here of either a diagram, a photo of the ICE with parts circled, or a picture of the connector and maybe where I can find it.

If nobody has these pictures / diagrams, I will try to take some myself and post them. But I am not the expert. I am just an owner of a 2007 Prius who has a knack for figuring things out.

Thanks.

#P0A4C
#P0A4D

 

[MarOmega]

So first off, I want to thank everyone for their help jumping right on to post diagrams and pictures since my last comment on this thread.

I dug around and found for myself a diagram (not pictured here yet) of the wiring going into the generator.



First thing I had to do was remove the plastic cowling from under the hood.


What I found were the connection points where the generator is plugged in. The orange shrouded high voltage wire and 6 wires going into a connector were where the problem was found.



As you can see here, rodents of some sort had chewed through my wires. After looking it up, I found that it is a common occurrence, since green cars use bio plastics. Other plastics are inciting to rodents as well, so it's not just localized to hybrids. But bio plastics are extra tasty.





Before going forward, I disconnected the safety power plug on the Hybrid battery, located behind the back seat driver side. (orange plug) and disconnected the negative terminal to the 12 v battery.




Ultimately, I attached 6'" jumpers, butt-spliced 14 ga wire, to the connector, and then crawled under and spliced them back to the harness. Matching colors is always a good idea to reduce errors.



I straightened the copper and plastidipped the high voltage wire to keep moisture out and electricity in.




This cured the problem 100%, but 20 minutes later, I got a check engine light, followed by the ! light. The codes that pulled were P0011 and P0013 indicating a crank shaft wiring issue. I had to park the car. Now I have to find a diagram for those sensors to see if they have been chewed as well.

 

[knon]

Jump starts

2009 Toyota prius. Fine for two years then the last five years it has required jump start over 15 times. Dealer says I do not drive it enough. Lately the screen lights up with all the warning lights but still will not start. Hook up the battery charger and away it goes. Battery cannot be dead as motor stops (as it should) at stop signs etc. Taking it into dealer (250 KM aawy) in August. Anyone else have this problem. Thanks for any advice you may have. Feel it may be computer but not sure.

 

[Francis Ying]

Phoenix, my 2008 Prius, 200K miles, won't go into "ready" with all warning signs on. I took to the dealer and got POAA6 failure code. I replaced a used tranny from reputable yard that offers 3 months warranty ( part n labor). nothing changed and same problem remains. break sensor, 12v battery, hybrid coolant pump, dashboard wire connections, all being checked. I can use a scanner to erase codes and warning lights to obtain "ready" back and drive, but those warning lights soon reappear and once I shut down, car won't go into "ready" again. I can also trick hybrid system fuse to obtain "ready" back to drive. what is next step I should take.....?