Prius gen 2 wont start

Good night,

So the story on this one is that i got my cat stolen on private park, so i sent my prius to my local toyota dealer
after sometime because of insurance that cat replacent extended to 6+ months. When toyota when to replace the cat, suprise suprise the car was complely dead.

After quoting me a 4+ grand for the job ( new cat, and hybrid battery), i (worked on alot of cars and was complely certain i could do this job) got the car towed to my driveway and started working on fixing it.

Cat was a breeze, hybrid battery on the other hand is giving me a hard time..
So after i replaced the battery, (both 12v and hybrid) and went to start the car and it was normal for some minutes. And i got it to neutral and was able to drive on eletric only. The thing is i wanted to start the motor to give the new cat the time it needed to adapt on idle.

When i tried to fire up the engine, i heard massive clicking sounds at the back of the car (kinda like a relay but louder) and boom triangle of death along with warning light to the "main" 12v battery. i tried a couple more times and it was the same thing all along but now it is saying that i have 0 charge on hybrid battery and can't get it to drive on eletric only it is just stuck on this. ( before trying to fire it up the display screen was giving me more than 50% charge)

I supose the 12v battery must be the problem since it came wrong and will need to be replaced, i am just wondering if there is some technical stuff that i need to do..

I also mesured each individual module before assembly and it was all 7.8v with a few at 7.5v nothing out of the normal i think. The toyota dealer ship mentioned the control module for the hybrid battery and that it could have gone bad, i just assumed that was dealers bs trying to get some money, but i think it is time to consider that possibility.

I appreciate any advice and thoughts you could give me.

Thank you.

 

Hello,

So today i got to work on a few things you guys said, first i checked the connectors on the HV computer and it was all nice and clean (no spec of dust or corrosion) so i ruled that out.
I got a new battery but i came wrong again, so i hooked that in paralel to the last battery and gave it a charge with my charger just to be on the sure side.

I also got the cheap obd scaner i normaly use for my other cars and i got some readings- main codes it spits out a P0A80 " Replace Hybrid Battery" . And some o2 sensors and cat module sensor ( i belive its because it never ran, so it never got to read anything).

So here's what it is doing. I press to start and the battery gave me one bar above 50%, and i (after cleaning error codes) turned on the car, after some time (Now it only "clicks" one time) it got ready and i had the handbrake on( i forgot it was on) on only eletric tried to go foward it went and then it stoped (bc of the handbreak) and shortly after shuted down. some thing were happening at the same time so, i put it in neutral and the car was going kinda crazy like "pewpewpew" and displayed a message "to park the veichle put it in P park ! " .

So second try was error codes all came back, triangle of death and a battery icon with "main" red. I would also like to point out that the battery is displaying now 0 charge completly 0. At this point the car didn't even try to get "ready" and wasn't clicking at all...

I unpluged the white connector on the 12v bat and waited.. After some time i plugged in and it was displaying again the normal (expected) so after one only click on the back i tried to turn on the actualy ICE motor.. 0 response- With the veichle diagnostic saying the voltage is 12.8 and it doesn't change between trying it on or not.

At this stage i belive the problem is the computer that is shutting of the hybrid pack for some reason and it doesn't have charge to actually power on the car because the pack is disconnected..

What further leads me to belive this is that when the car tries to get on for the "first time" it has the correct lvl battery, but it changes after trying again.

I can't get my Dr prius to actually connect to my scaner so i can't get each module voltage, but since i got all the modules out yesterday and there were nothing to worry i doubt it has to do with the actual modules/pack.


Notes: I am using torque pro to check codes.

 

Tomorow i will try to get a reading on the SOC and each battery module as i found a way to do it on my scaner now

 

Update

Okay so all modules are arround 14.4 - 15.1v, expect for one that is at 9.9/10v and 2 that are at 11v

New fault code- P0AC0 - I googled and it appears to be a problem at the connectors/controle module?

I also noticed that when i start the ignition to get readings, the HV SOC starts at arround 60% and then drops gradually till 0.

HV POWER is at 0 kW
HV CURRENT is at 0.2 Amps
HV CHARGE is at 16.0 kW
HV DISCCHARGE is at 64.0 kW

I got some screenshots, sometime after the first power and at the end ( SOC changes to in that span of time)

and

I will remove the battery again and mesure each module to find out were that 10v is and charge it.

Also does the 12v battery have to be original from toyota? Can't just i get some aftermarket one?

Thanks.

 

I think you can see this now, the problem i have is that i already replaced the modules that were below 7.5 (2) and when i installed the pack the lowest cell was at 7.3

I really don't want to spend more money on more modules..

 

I would like to point out that i missed the orange plug on the Control module that was around 3 pins with slight oxidation so i cleaned that right up and will do some more work today.

 

Good morning.

So MEGA update...

I ended up buying a 12V battery from the dealer, dissambly the battery and checked each individual module, let them balance each other out along the weekend.

After installing it the car started right up 0 problems.

Since then i have been doing some tests, so far i noticed a problem.. When the SOC% gets to arround 29.5/30% the triangle pops up and i get P0A80...

The overall functionality of the car is OK , the Km/L seem withing range, Still need to run a little more to get the full picture.