Chevy Lost the VOLTS? (HV Battery DISABLED - P1FFF P0AA6) 

I often work on these cars. They're pretty easy once you learn what you're doing. Unless I'm missing something, you never checked if the coolant level sensor was faulty before trying to clear the code or flashing the module. I've gotten burned on that before. Also, needing to reprogram the module to clear the code is a bug in the software that GM never fixed. It wasn't designed that way. They were just too cheap to get their engineers to write new software that fixes the glitch.

My 2012 GM/Holden volt did this about 18 months ago not long after it had a full coolant replacement by GM/Holden dealer. A Google search showed this to be a common issue. I simply added about 100ml of dex-cool to the “anti-tamper” tank (coolant line above side sticker) then reset the trouble code. No problems since with approx 20,000km and stored outside.

Congrats to the owner for finding you. He got lucky on this, some dealers would have gone crazy even w/ TSB on hand.

The best PHEV ever made that no one knows about. GM was way ahead of their time with this one. The Prius Prime of its day. Too bad they killed it. Good on you for taking it on and good work as usual.

As usual , logic , correct information , and a talented tech who enjoys learning and a challenge

I am impressed of your skill and tenacity to complete a job you take on. I don't always get what you are doing but still find it fun to follow!

Great fix Ivan, this really demonstrates the importance of technical information. Without that Tsb this fault would be nearly impossible to fix. Keep up the great work i really enjoyed this one!

Ivan staying on the cutting edge of automobile technology. Impressive !

So Toyota has the Triangle of death and GM has a coolant tank and software issue, both are luckily repairable. Just have to be like Ivan and sort thru the maze of bulletins, description of operation and wiring diagrams, easy. :) Nice work Ivan!

EVs are weird! And a whole new range of (expensive) problems come with them - reprogram a module to clear a DTC? Good job, Ivan!

Thank you Ivan your videos are always great! All of us especially appreciate the programming shown in the videos! Rock on Big Ivan!!

IVAN, YOU ARE ON THE TOP OF YOUR TRADE WILL EQUIPPED TO THE LIMIT; WITH ALL YOUR NEEDS TO DO A BETTER JOB THAN MOST PROFESSIONAL SERVICES IN THE INDUSTRIES. YOU HAVE A GREAT KNOWLEDGE TO BE NUMBER ONE. VERY IMPRESSIVE.

All is completely over my head yet both daunting and intriguing. My overall reaction is you are more detective then anything else. Way to go Sherlock! :)

Had one with the same code, reflash the module and all good. Great video

Да , на моделях 2011-2012 года, на которых датчик уровня был доустановлен, ошибка P1FFF сбрасывается при sps программировании. На поздних можно уже через диагностику. Если ошибка по низкому сопротивлению изоляции будет повторятся и нет утечки антифриза в батарею - необходимо заменить подогреватель антифриза, он находится в батарее.

This is awesome work! Молодець! :) A couple of suggestions if I may: -- tilt the laptop screen down to reduce reflections and glare; -- press F11 in the browser to go full screen to show more content and reduce scrolling. Hope you get a chance to work on more plug-ins. The owners could really use your help.

Awesome video Ivan. It's great that you're touching EV stuff. Keep them coming because in just a few more years we'll see a lot more of these cars.

You're a legend. Please don't turn into an advertisement for a virtual private network

Software updates to fix problem. The not so new way to fix vehicles. Good one Ivan.

PHAD: (posts video on a broken/disabled EV) The RU-vid Algorithm: "I know JUST what to do with YOU!" (inserts ad for Lexus EVs)

And this is the Future of cars!!!!!!!!!!!!!!!!

Ivan, this made me a bit nervous just watching. You're working in an area of expertise very foreign to me and it's a bit fearful seeing what automotive repair has become. Not quite like the days when you listened to the vehicle run, adjusted the carburetor a bit, and sent a satisfied customer down the road. Thanks for Sharing! P.S. I didn't even see you use any hand cleaner once the job was done!

Good job Ivan, always impressed with what you can do. Two thumbs up.

The Volt is a great car . My friend bought a used one about 7 years ago and he has had zero faults. Odd they stopped making them.

First EV and looking good.

Ivan, i ran into this 6 months ago and it was a 2012. The Level Sensor was faulty, the customer replaced the level sensor and bought it back to me to clear the DTC, of course it would not clear. I told them they needed to make an appointment with Chevy to clear it.

I have had this issue on my 2023 Volt and I just cleared all the DTCs with my 500 dollar scan tool bought on Amazon.

At least you can do the programming and it's not that expensive - many manufacturers have this sort of crap as "dealer only". Plus you have access to the service docs through AllData (and they seem pretty good). For some manufacturers (I'm looking at you BMW) you can't even get the service data, only through their software, which costs $$$$ - or you just pirate it which is what most people do (see your Maserati series...)

Before even watching the video I want to warn you you have to flash HPCM2 to clear faults. Their is a TSB for like along with the isolation fault

Good job, lots of technology you had to use. You are the best.

You can use the shvcs defeat plug to deal w/ the coolant level sensor to bypass it, but reprogramming is still required.

Where may I ask did you get your training as you are very thorough? Oh, I just found your shop and the education and your self interests and need for the hands on and that you found your niche in electro mechanical repair as your bushiness. Very good, Ivan. I kind of thought it may have been close to what I did.

Great job as always, better to pay ur programing fee than GM, what about a charging fee? im sure u just did a quick test to see it works

Those Chevrolet VOLT vehicles have a very common failure on the HV Battery coolant reservoir level sensor. When the sensor goes bad, it locks the charging system to the HV battery. You have to replace the level sensor on the reservoir, or also is the option to bypass it. Very common failure on this vehicles.

Wow! Great video...just pulled both of these codes on my 2015 Volt I live in CA and I understand that we get a 10 years 150K warrantee, Q> would reprogramming be covered under warrantee at the dealer? Love to find a person like you near Los Angeles, CA you make sense of everything.

WOW...awesome job and video it was a learning experience for me..and another reason why I still have my vehicle...

Thats crazy that you absolutely have to take your car to a dealership in order to reset a check engine code. But that's no software bug. That's job security right there.

Nice video and diagnosis. I guess you better learn all you can on those electric cars since they are getting older and problems are showing up.

Thanks for learning me something. What did the programming cost? I pay 42.9 euro +21% vat, so around 50 for peugeot/citroen (PSA Europe)

That's crazy, but well done!

SAVE THE SPS CAL FILES IN THE SPS CACHE FOLDER then you can use Gm DPS to program any other car and you don’t have to pay gm any money if you want to program a different VIN BUT THE SAME MODUEL you can use the cal files to create a archive file for programming. in the cache file will be “for this ECU 3 bin files” 2 of which are the cal files which is stuff like boot and operational software the other is called a utility files it acts like a instruction set for dps to program that specific module It can also do other cool stuff with type4 like odo correction 😉

After reading through a lot of the comments it would seem to be a inherant glitch built in to be a saftey feature albeit a very costly one to rectify.(Also to keep stealerships in the money loop.)

Hey Ivan after going through that whole fiasco with having to reprogram to clear codes, what is you take on owning one of these???

GM should not charge for an software update for that fix. From the TSB standpoint, sounds like a known problem that GM wants to collect on.

My question is did the reprogram actually update to a new version or just overwrote with the same version?

i think that any manufacturer that has a update to fix known faults the update should be free as they could set up a timer on every car to get money from customers ie held to ransom soon as it is known they fix for free then they loose they may get better reliability first time

Similar issue happened to my best friends dad's car. 2012 volt. Had him bring it by the shop, he told me this is the third time it happened to him, first two GM covered, third one was out of warranty. He only had the coolant level fault along with the contractor opened from the fault code. Coolant level sensor read something like 1.2kohm when low, 6.8kohm when at the correct level. Not your standard closed circuit when low, open when at the right level. The magnetic float internal to the tank had gotten coolant in it, replaced the tank because of the float, and ran into the same problem. Couldn't clear the code, I couldn't reprogram it at the time from not having the hardware, and still had to send him to GM to get the module reprogrammed after the repair. Never had to reprogram a module from a bad coolant float before. Just ridiculous.

I wonder if that is to keep people from getting a code scanner and continuously resetting the code when there really is a problem resulting in battery damage and possible fire. If you have an EV or hybrid, do not under any circumstance mess with the batteries unless you are a professional. If they go into thermal runaway you will be very sorry.

Good repair Ivan

Wow.. They should have to do that update for free, as a recall or something. This is ridiculous.

This video is a perfect example of why I am never buying an electric car. Almost anything to do with the high voltage systems requires online programming and several manufactures do not even make the tools or software available outside of the dealer network at all. They use "safety" as they reason why they say non-dealer repair shops are not allowed to work on HV repairs

A Volt can identify as a "regular car?" Too bad a Prius can't do that. Great video!

Since the problem was in the programming, the only way to fix it was reprogramming, makes sense.

Relocate the sensor from under the reservoir and wire it up next to the HPCM2. you can locate the two wires with your multi meter set to continuity or buzz and they will be next to each other on connector. The problem with the car is the LONG thin wire to the sensor when powered up is only 3.5 volts on the power side and connected to a 24K ohms resistor " way too much" and the module is looking for a voltage drop to disable charging, module is made to not charge once voltage drop is detected. They made this circuit so the module would be looking for a voltage drop on a supply of only 0.00014 amps. come on GM ... If you put the sensor under the passenger seat keep an eye on the tank level for leaks. PS the dealer had my car 3 times and couldn't fix it there next step they said would be $2200.00 to drop the battery and check the modules.

I hadn't thought about that. Do the hybrids keep TWO set of numbers for how many miles each engine uses?

I'm there now. I have a Volt 2012. Let it sit for 7 months in Oregon, rainy climate. Possibly messed up my sensors. $1,000 bill today for nothing at a Chevy Dealer. They wound up clearing the codes and put in a 12 volt battery replacement. Not much return on that -- said I' need a new HV battery if the codes return, yet none of the cells are defective. Low coolant good. He missed something.

How much is the programming fee? And where did you download the program? As i want the same stuff lol. At least the Volt has some power back lol. It's now volting!! Hahaha. Great job Ivan. Sounds complicated to diagnose it when it's requires programming!!

Is there any idea what caused the fault besides sitting around for two months?

Good grief! That's insane.. have to program it to clear it? 🤦‍♂️ Good ol GM. Well, sometimes you need to visit a junkyard for parts, why not programming too.

I used to love GM products, but not anymore. My last was a Cadillac. Full of electronic glitches. Never again! Just don't need the constant "Dealer Headaches".... and expenses!

Just waiting for all these car to get a bit more mainstream and older then the DIY repairers getting into them, fires, burns and anchors will be a plenty.

First, the coolant level was not full. Should be to the top of the black label or the problem may return. Second, it is a 2012, which has a coolant level sensor spliced in by the dealership. These get corroded over time and need cut and soldered.

A very green car except for the mining of lithium and generating electricity to charge it 😆

Thanks Ivan!

Maybe you can help me too. Looking to purchase a 2013 Volt, won't charge, dealership said cells 1 3 and 4 are low. Looked at car today. 12v battery dead, jumped battery with running car and now fob works and display reads service high voltage system. HV level shows 0%. Dealership pulled HV isolation code. Vehicle has been sitting since last November. Could it just need a 12v battery and a program? Thanks in advance for your help! I'm a mechanic former GM dealership but never worked on these Volts.

I wouldn't have thought that would go through with the Engine running, I guess you found that out as you turned it off half way through programming?!

It is good to show how to re-program if the Brac is reset by mistake

Hey Ivan, I'm a little late to the party as usual, but I was just wondering why you didn't check the battery drain since you had to do the reprogramming anyway? I'm not trying to be a dick, just wondering. Another great video as always! 👍🏻

How did you get tech2?

My Chevy Volt 2012 with 105000 miles was charging as usual, last week the charger showed red light and I’ve got an engine light on. I brought it to the garage, no diagnostic was given. they said it could be a faulty charger cable. I tried to charge with other cable at a public ev charger and it also went red. It doesn’t charge. I suspect it might be the charging port since the battery doesn’t run low in volts and keeps regen. I am about to order a new charging port for a diy repair, the new part costs about €315 (340 usd) to import here in Europe, however, I am afraid i will have to bring it to a dealer to reprogram if the error doesnt clear, which might cost a lot. And I can only hope that changing the port will solve the issue. Any ideas or suggestions before I get myself into the challenge?

Good Kieth question?

It would be interesting if you worked on some fully-electric cars. I'd like to see what kinds of issues they have once the warranty expires.

I have a 2011 that won’t display the mileage, any help would be appreciated.

I was told to consider the module a electronic breaker and like any breaker it must be turned off before being turned on

the fluid level for battery is to low buliton on that hit a bump it can set code

I'm looking for a scan tool to reprogram keys, ECU, and EV like you're. Can I have the model number of yours please.

I love your videos and your work Ivan, but I get a little restless when you scroll back and forth looking for codes and descriptions. Cant't you just press (CTRL+F) and type in what you are looking for in the search field? Or maybe it is not possible ???

What kind of scan tool do you have?

Good morning all.

When you tried to reset the codes with the scan tool and it couldn't do it because it said "High Voltage Battery Circuit Contactor Not Open" do you think that means you needed to pull the high voltage disconnect and then see if it would reset. Just a thought.

Can you keep the module file to reflash next time?

There have been some cars I've seen that have solely just needed a programming or a software update to get the vehicle running. I am not against software updates but if the system is rigged to force drivers to into getting updates whether they like it or not, I don't think that's really fair. I speculate they might be de-flashing random people's ECUs through the Sirius XM radios or something (not speaking for this case study).

I just got these two codes on my 2013, and it would not charge. I was able to reset the codes with my Bluedriver and now the car charges.

What a nuisance design, hopefully people will 'Charge away' from this car :-D

Mr Ivan is there a way I could somehow get a hold of you? Really would like your help. Honestly I’d appreciate that very much

It’s all about the money

Great video! Does anyone know someone in Minnesota that can do that ? (Outside of a dealer)

Anyone knows what is the Flash Programming Voltage for a 2013 Mustang GT?

i had this happen and they replaced the coolant sensor. fixed the issue

Where are you located?

With batteries and water/coolant gmc is erroring on the side of caution…

They have a $120 bare bones tool for use w a phone perfect. Thinkdiag OBD2 Scanner Bluetooth

Any way you need to pay.for the reprogramming 😅

Coolant level is still low. It’s suppose to be above the black sticker.

Hi , man how I can contact with You. I have own Chevy volt2 and have same issues with my HV battery. Before techline was affordable, right now in Europe I have problems with reprogramming this modules. Can You help me with this ??

Leaking coolant on between the cells?

How we as diy folks be able to get the programs from oem?

Self identification is the thing these days 😀

You would think the lithium and coolant might cause a uncontrollable chemical heat reaction ?

So the problem, is basically from the vehicle sitting too long and not being driven, causing the error code that could not be cleared without reprogramming...