Check hybrid system

The entire pack sells for that amount and more, but inside there are 34 individual batteries connected in series. The cell I bought has a good voltage and is an exact replica of the battery cell I replaced. I understand the risk associated with opening it up and work on battery strings with a much higher voltage on a regular basis.

Knowing what trouble codes are stored in the computers is key to diagnosing a Hybrid System. Since you cannot start this vehicle and take it somewhere for further diagnosis try disconneting the 12 VOLT battery for about 10 min. Reconnect and let's see what happens? Are you sure there where no sparks while you were performing this repair?

I reset the maintenance through the dash and took off the battery connection for 10 minutes, with no progress. I tried plugging in an OBD2 and it does not connect. I figured out there is no power to the port to check the codes. I pulled all of the fuses I think could be related under the dashboard. After some research and trouble shooting I narrowed it down to the fuse bus bar under the hood. The 120amp fuse blew and the fuse box must be removed to access the bolts underneath that hold the fuse down. To access I had to remove the air box and the inverter. It was very time consuming, and I got it out. Picked up the new fuse from the dealership today for $24. Will update when I get it installed.

WOW...I'm impressed with your persistence. nice job with your diagnosis. What worries me is what blew that 120 amp fuse? That is a big spark. One could weld 1/4 inch steel plate with that current. May I suggest you use a lot of caution when installing that fuse. Check both sides of where the fuse plugs in with a Volt Meter. Make sure both ends of that fuse connection is at near ZERO volts. I she blows again...you might consider going back to square one. A pair of electrically insulated gloves might be in order. If you do get into that HV Battery Pack....look for corrosion among hose module connections. Rather common cause for Battery Pack replacement. Keep us up to date on this interesting issue.

The new fuse is installed and the car started up. I still have a check engine light, but was able to use the obd2 scanner and get the codes. The check engine light was on before I started this project. The car sat for a week with the batteries disconnected. (P0441)The first code is for the evap system which has a lot of scenarios to fix it. I will work on that later. The second code (P0A9E) hybrid battery temperature sensor "A" circuit high. When installing the battery pack one of the sensor wires came loose on the bottom of the batteries, so I believe that's my issue for the alarm. As for the fuse, I have class 00 gloves and a multimeter along with insulated tools all rated at 1000 volts and a 40 cal arc flash suit. I checked the copper bus ends on the fuse and the incoming wires. Everything was dead before handling and taking apart. The batteries were also disconnected, LOTO. As for the short that blew the fuse, the black wire that comes from the negative pole on the 12 volt battery and gives power to the components inside the hybrid battery shorted with ground. The connector they were fastened to was twisted a little and not properly placed within the hybrid battery pack. It is a small white piece of plastic connected to the frame. The car has charged back up with normal driving and runs fine. When starting the car the first time after the fuse installation it took a few minutes to get all of the components back online. Now that I took it apart once it will be much faster if I ever have to do it in the future (my sister has the exact same car and hasn't had maintenance on the batteries yet). My only regret is not getting pictures of all of the dissembling, but when working in the engine I had grease all over my hands and did not want to touch a camera or phone. I'd be happy to assist if anyone has similar issues with their hybrids and has questions. Glad I did this repair myself.

U RAA...AND GOOD FOR YOU. Keep us up to date on your continuing adventure with this vehicle. Concerning that battery temp code. I seem to recall a Toyota service bulletin concerning cleaning a dirty HV Cooling Fan. Good Job...and ...Good Luck.

Thank you, I'll look up the service bulletin.

Aaron....any updates on this vehicle?

The Camry started hesitating again during normal driving, so I assumed another battery cell probably failed. After taking everything apart and testing each battery individually the voltages were about even. The only way to find the bad cell would be to test under load and check the resistance of each battery. Using a alber cellcorder I was able to narrow down the batteries causing the issue. The car is running as normal and no warning lights on the dashboard.

Once again...im very impressed with your persistance with the repair of this vehicle. We are all learning from your experience. Did you perhaps notice any CORROSION at the individual battery cell connection. As you most likely know..corrosion....not only causes resistance to current flow....but aslo Heat. There is a seperate cooling system for that HBP. Another Toyota Service Service Bulletin indicating cleaning procedures..

Btw...another thought. How would one Load Test each battery cell to help with the diagnosis and testing of same? With a 12 volt battery the rule was...load the battery to one half the Cold Crank Amps indicated on said battery. ....for about 5 seconds. Terminal Voltage should should hold at no less than 9.5 volts.

There was very little discoloration on the copper plates that link each positive and negative terminal, the first time I had it apart. All of the terminal posts looked clean, but I used a wire brush and clean cloth to give the posts a quick clean while I had it open. As for the copper plates, I soaked them in white vinegar for about a day or two and then gently sanded them each down until they were smooth and shiny. I wiped them off with a wet rag to clean any remaining particles or residue and dried them before rebuilding the battery pack. The cooling system works well with all vents clear and fan spinning freely. I did wipe them out with a microfiber towel to get any dust that may have made it’s way in there over the years and during the dissecting and reassembly. If you test the batteries individually you can use any machine that would use a 12volt battery, and connect with alligator clips that are rated properly. Or using the appropriate meter just test each batteries resistance across the terminals. You’ll be able to tell which ones are bad by comparing to the average number of the rest of the batteries. The bad cell will have either a really high number (most likely) or a really low number compared to most of the cells in the HBP. Thank you last_chance_garage.

Ok....got it. Nice job. Keep in touch with futher updates. Thanks for the tutorial....LCG

Will do.

i have a hybrid 2007 toyota camry ,my check hybrid sistem is on,i already service the battery,i had 3 bad cells,how can i reset this sistem?

Did you happen to record what codes are stored in the computer?

no,the check engine light is off,so i though that wasnt,nesesary,do u suggest me to throw the scanner to it?

i dont know but i have the feeling that i mixed up the batteries secuence,because i noticed that some cells have some sensors or wires at the buttom,i loose almost all of them in order to replace the bad cells,the car runs great now,but still have the check hybrid sistem and tire pressure light on,any advice?

Suggest you scan for codes and record the codes description and ID number. Get back to us with results.

HI , I HAVE THE SAME CAR , TOYOTA CAMRY HYBRID 2007 . CAN YOU HELP ME Yesterday, I accelerated my car very fast after making a stop, when I came back to stop and start the car I failed a bit to accelerate and it appeared that I check the hybrid system. What could be the problem ?

Suggest you have the computers on your vehicle scanned for codes. Note the description and numerical values and get bsck with results.

Hi I have the same issue . I just don’t know for sure if it 120amo alt fues or not My car don’t turn on Work: lights turn on , dash , Not working : mirrors, power seats , break panel , radio etc . How to make sure what is the problem wt my car , and how to replace the Alt fues ? Thanks

The alt fuse is usually located in the fuse and relay box located under hood....driver side. This fuse is bolted in and sometimes requires removal of the fuse box. There shoild be a video on line describing the procedure. Google your make ...model...year....and Alt fuse.

I have the same "Check Hybrid System" light. I had the hybrid battery replaced about 8 months ago and all was well. Then, about 5 months ago I started having similar symptoms. Come to find out it was just the 12v battery. I replaced the 12v battery and all is well. However, the warning light is still on. I scanned the OBD system and there are no codes. I read on at least one forum that there is another electronic tool (scanner), not the OBD II, that is required to reset the hybrid system warning light. Is this true? Thanks in advance!

No, the best way to reset all the lights is to Unplug the hybrid battery ( unplug that orange plug ) Leave it unplug for 5 min . Or by 12v Or both . If this doesn’t work ? Listen to ur hybrid battery fan , is it always on while driving ? If no, Ur batteries are all good If yes, u still have a bad cell or ur cells are not balance . If unbalance cell , continue driving try to charge batteries up to 9 bar .... that should take care of ur lights soon

W87...what ever happened with your Hybrid vehicle?

Can you let a hybrid car sit for 6 month using only a 12v battery tender connected to the 12v battery? Or do I need to unplug the HV battery pack? Any other experience with this?

Aaron.......did you ever find an answer to your question?

No, just a bunch of guesses from people.

Toyota recommends starting their Hybrids once every 2 weeks and letting the vehicle run for 30 min. This will allow the hybrid battery to stay near fully charged. Toyota also recommends disconnecting the negative battery cable on the auxillary 12 volt battery when in storage. A battery tender should be OK for said battery. Interesting question. Let us know what you decide to do.

My 07 camry hybrid has the same problem. Check hybrid system is on. Battery is down, the service did a diagnose and told me 16 and 18 blocking, need to replace the whole battery for $4k. I can still drive, and has a second or two hesitation when giving gas. When it goes into electronic mode, I have to pull over and restart the car otherwise the engine sleeps forever. The reason war that I left the car rest for 2 months so the battery died.

My car had the hesitation also before dying on a daily drive, and I towed it home with a tow rope and good communication between the two drivers. (Pull vehicle and towed vehicle). Would you feel comfortable replacing one or two batteries yourself? It is high voltage. But the replacement cells cost about $40 a piece. I did see a video online about recharging the old ones, but didn’t attempt it. You can also get a company to come out and replace a few cells for about a third of the price of a $4000 replacement. They usually offer warranties on the replacement and will come out and replace more if the other batteries fail in the future.

I actually know nothing about car. I just talked to my friend who works for a dealer. He suggested not do it myself because hybrid system is too complicated and dangerous. I don't know how you are able to do in it, I mean, in details. I am totally uncomfortable doing it myself. I might consider the company that you mentioned. If it is a third of the price, I can accept it.

You should definitely look into a third party replacing cells, and get the warranty for a few years. A friend of mine went that route and it was $1300 with a 3 year warranty. Since the first replacement of 2 cells, they had 2 more change outs of battery cells. It’s a little less convenient, but saves a ton on money. I only changed it myself because I felt comfortable doing it, and would not recommend it for someone with little to no experience. There are a lot of parts and deadly high voltage potential. Let us know what you decide.

This morning I saw a new message on my car: Low T BATT, stop the car and switch to P. I switched to P for a minute and then the message was gone. I want to get it fixed ASAP otherwise it is too much concern. I would like to talk to a third party who can do this and see what they offer.

You’ll have to look up locations near you with google or another search engine. Type in hybrid battery repair and go from there. Check reviews and call to see what works best for you.

I found some battery sellers and they might provide installation service. I'd like to pay a visit to them after I do a regular car maintenance. One thing I am worried about is that it has been 2 months since the diagnose of the dealer. I don't know if more batteries go down in the meanwhile.

2014 Camry hybrid having the check hybrid system notice going don't know what happen and how to fix it?.

Van...the first step in the diagnosis is to have someone attach a Scan Tool to the computers on this vehicle and have the codes read. Some auto Parts Stores do this scan for Free. Be sure to write down the code numbers and descriptions then get back to us with result..

I called some battery providers but none of them have hybrid battery. And one told me that I got to ask dealer to get one. Then it goes back to the original problem. Do you know if there is any company with hybrid battery service in Vancouver, Canada?

When I Google your location and.....Prius Repair.....I see several repair facilities near your location. Give it a try.

Wow, what an informative thread this has become. Here is my problem. A few months ago I replaced 2 bad cells. I bought the $100 gloves and a multimeter for the job. Everything went well. Now the VSC/Hybrid lights came back on. This time the multimeter doesn't indicate any bad cells. I am not sure how to "test resistance under load". Can anyone shed light on this subject for a novice?

Hi I have a Camary 2011 got a error" check hybrid system" last evening.......can this happen due to low engine oil? I did not replace oil as I will be off for a while this month end so thought will replace once iam back ....but got this error ..pls. suggest

What is the mileage on this vehicle? Low engine oil light would come on if your engine oil was low. You need to have the computers on this vehicle Scanned for trouble codes. Some auto parts stores will do this scan for free. Write down the Code numbers and descriptions and get back to us.

Get a cheap bluetooth OBD2 port scanner and the Hybrid Assistant app for your phone. You can diagnose the battery while its still installed. Look in the app documentation for the Battery Check steps and it will generate a report that shows which cells are out of spec.

We are not in 1960 or 1970, that you can fix anything in the car and you feel very happy. This days the car is built with very delicate and sensitive instruments with electronics and computer. Some of you may have fixed your hybrid batteries but it's no so simple, there are other issues that links the battery with complex code and system. Don't become so confident that some of you are fiddling with modern cars and thinking it's running but in reality it is damaging other parts of the car without your knowledge. I am an auto engineer for thirty years and I know to fix today's cars, you need lots of knowledge and testing equipment. Don't just try to be clever or to save money. It's not worth it.

I have 2008 Camry hybrid. It shots off while driving. Any idea or suggestion please?

Any warning lights on or flashing when the engine is running?

Aaron.....hello again. Its been awhile. Is that Hybrid still running?

I have a 2007 half hybrid and have gas. Hybrid and engine lights came up at once and 24 hours later went off. Any suggestions?

Make...Model...Year? When warning lights come on....even if they go off....there is a problem...a...coming. Suggest you take this vehicle to a Auto Parts Store that will read Trouble Codes For FREE. Wright down the code numbers and descriptions and get back with results.

It’s TOYOTA Camry

Hi Aaron. Have read your posts about fixing your hybrid system and you have an impressive amount of skill and knowledge. I would like to run something by you, if I may. We have a Toyota 2015 Highlander Hybrid. We had a badly cracked windshield and we had the dealership replace it. Within a week, our Highlander coughed up some warning light and a message to immediately pull over and not drive the car. We had it towed to the dealership where we were provided with a rental(paid by dealership). When we got the car back we were told by the service department that they had installed an aftermarket windshield and that it had leaked when it had rained and damaged the hybrid system. They replaced the windshield with a Toyota windshield and replaced other things under the hood. A week later the same thing happens and back we go to the dealership and a rental(paid) and they tinker around and we get the car back. So, we go on vacation for a week and while away our car has conniptions again and we called our dealership who put us in touch with a closer dealership. This one picks up the car, clears the codes and says there is nothing wrong with the vehicle and back it comes. I get in touch with our dealership and with Toyota Corporate to bring them up to speed. I share my concerns about the car going tits up when we are to come back from vaykay with a fully loaded vehicle and our dealership assures is that because we have five more days, there is a good possibility that, 1. The car will die again and then they will get us a rental and have the car towed to them or, 2. The car will It code and we will get home without problems. Last day of our vacation, we load up the car, jump in and damn if it doesn’t start. We had been using the car all week and it coded on the last day. Long story long, have you or anyone else experienced this kind of problem? The dealership seems to be learning as they go along. We are terrified about keeping the car. We want to get it fixed properly. We want to keep the car but do not want the headaches nor do we want to pass it on. Help. Thanks.

Similar issues with a friend's 2012 Camry Hybrid. Throwing P3190 P3191, as well as check hybrid system & P0A80, P3000, P0A0F. Bypassing the fuel pump relay (running the pump direct from the 12v) seemed to eliminate problems; No fault codes, engine runs fine, no check hybrid system, HV battery chargied to 60%. Working on a (semi-)permanent solution with an ECU triggered relay (assuming ECU is ok, and the issue is further downstream). Did recondition the HVB cells with a hobby charger, didn't make a difference, the issue is somewhere else; like bad sensor data, or possibly an actual problem. BTW I'm a technician, not at all mechanically gifted. Any help is massively appreciated

I have a 2009 toyota camry hybrid. The batteries wont charge and my check engine is on the code tht is giving me is P0420. Do u think thts the reason why my batteries are not charging