Engine lights off but can not pass smog due to permanent code

Weird, I can't even find a P0A11 code listed in the Toyota Gen 2 Prius repair manual. This code has come up previously on the forum and there's always been the question of whether it's truly a legit code or a misread by non-toyota software. May want to actually get it checked by Toyota and see what their diagnostic equipment shows.

 

What year Prius do you have? I am not aware that any Gen2 Prius (2004-2009) has "permanent codes" - the government added those to OBD2 in 2012.

Posted via the PriusChat mobile app.

 

My 2010 supports permanent codes.

 

You mean that google is wrong? "shock"!
Then I wasted a whole 30 seconds looking that up. (sigh)

Posted via the PriusChat mobile app.

 

How old is your 12v battery?
P0A11 - OBD II Trouble Code

 

I haven't looked for the details. One possibility is that a mandate was put into law to become required in 2012, but manufacturers were given some advance notice to build it into product lines, like Gen 3.

 

That link is broken – 403 forbidden error.

 

Problem with your ISP?

Still works
P0A11 OBD-II:
DC/DC Converter Enable Circuit/Open
What does OBD-II fault code P0A11 mean?
OBD-II Code Engine may not start is defined as a DC/DC Converter Enable Circuit/Open

The Hybrid Vehicle Converter converts high voltage from the hybrid system to 12V so that the auxiliary battery can be charged. It also allows the High Voltage System to supply power to other areas such as vehicle lighting and the radio. If the engine control module (PCM) detects a drop in voltage on the auxiliary battery, it will set code P0A11. Failure of the DC/DC Converter may result in the vehicle stalling.

 

The funny thing is that code shows up online in many generic "auto-help" websites, but IS NOT listed in the Gen 2 Prius Toyota Repair manual.

 

Permanent codes are a new thing in 2010 and newer vehicles so folks are not up to speed on them yet. With the check engine light off and a permanent code present does not mean there is anything wrong with your car. It means there WAS something wrong with your car and those codes are going to stay around a while to make sure you fixed it right. If not for a CA SMOG you can basically ignore Permanent codes they are not hurting anyone hanging around inside a ECU.

You cannot clear a permanent code with a scanner or battery disconnect.

You can pass a CA SMOG check with a permanent code in place as long as you have these items in place:
No Check Engine Light (meaning no current codes)
Monitors Complete (Except for EVAP, that can be incomplete)
And this is the important part: Driven 200 miles and have 15 Warm Up cycles since the last time the DTC's codes were cleared.

Now doing this 200/15 task will not clear the Permanent code but rather the CA SMOG machine has been programmed to ignore the
Permanent code if 200 / 15 is complete.
Cant post link but look up PDTC on the CA BAR site

Warm up cycles are simply the engine getting up to a normal operating temperature then cooling back down below a certain temp. Below is a video of a guy forcing them on a car with a fan to aid in cooling things down. This can be done in your driveway if you want.

The standard for most cars is Up to 160 degrees then it wants to see a 40 degree difference. So cold start up to 160 is 1 warm up cycle. Cool Down to 120 and back up to 160 would be #2. But could vary depending on the car.

Most scanners should have the Data PID's that will show you how many warm up cycles you have done and how long you have driven. If those are better than 200/15 you are good to go for a smog. Look in your "DataStream" or "Live Data" list

If you go for the smog and the inspector turns you away because of a permanent code tell them to kindy run your vehicle through the test. It's not thier job to save you from a fail. They are to run the vehicle as it is presented, that is what the BAR tells them.
If they wont give you a test file a complaint with the State BAR and keep trying at another inspection facility. I got a guy with 4 complaints in on shops.

Youtube video address: v=gswP3KlmfdI

He even mentions the Prius in there as it is such a common occurrence.

 

Also, if you're just looking at, like, one permanent code and you're impatient for it to go away, you can always look up the Confirmation Driving Pattern for that code in the repair manual, and then just go drive like that.

Toyota Service Information and Where To Find It | PriusChat

Depending on the code (they all have their own confirmation patterns), you can often get it sorted that way in a lot less driving and a lot less time than just blindly driving 200 or 500 miles and crossing your fingers.

 

There is some debate around that approach. As if it were that easy CA would not have had to come up with this 200/15 rule. I have seen people try to drive a drive pattern 20 times and still not clear a permanent code. Some speculate the ECU wants to see similar conditions as to when the original error occurred. And in some instances that is very hard. Like say you went on a ski trip and the morning you started it up a fault occurred at -10 degrees. Then you drive home to a location with an average temperature of 70 degrees. And all your start ups are at that temp for the next few years. If part of the clearing criteria is it wants to see a temp similar to when the code was set then it will never celar it. I have seen fords description of permanent codes and they say it will clear with 3 successful monitor cycles or even one if you clear the codes. But if that was the case people would not be having these problems of them hangin around.

 

The only time that happened to me, the explanation was quite simply that I was looking at an old edition of the repair manual that had a step missing in the confirmation driving pattern. It was solved when Elektroingenieur looked in the current edition online and told me what the missing step was.

To be sure, that wasn't the only goof I've ever seen in a Toyota repair manual, but I could still count all of 'em I have seen on one hand and have fingers left. Most of the time, what you read in the manual you can take to the bank. Especially if you look in the current online one in case of any doubt. They do catch errors and fix them.

Toyota Service Information and Where To Find It | PriusChat

On the other hand, I would have run out of fingers and toes long ago if I tried to count all the posts where people aren't looking at the confirmation pattern in the manual, and instead slinging assorted voodoo for trying to make their permanent codes go away.

 

If you need a copy of the repair manual for your 2008 Prius, send me a PM and I'll reply with a link to the manual on my web site.

JeffD