Having trouble with HV battery.

About 4 or 5 days ago I got the dreaded red triangle of death, so I took my car home and parked it.

I got tech stream out and connected it to the car to see what the problem is, it returned codes of p3000 and p3009, under hv battery live the 3009 code reads leak detected.

I reset the codes, turned the car off, then I turned it to the on position and waited, the warning came back, from what I understand if the car is in the on position and not the run position that means the issue is in the hv battery.

I tried to toggle the battery blower fan on and off but the battery blower fan will not turn on at all, I do hear a relay flipping in the battery but nothing happens.

I took the battery apart and cleaned all the bus bars and re attached them, then I watched the voltages on the battery blocks, they would charge as high as around a bit over 16 volts with the engine running, and they would slowly drop to around 15 volts over about 10 to 15 minutes with the engine off before it would start up again.

when I had the battery apart I did check each cell with a multimeter, they all read around 15.5 volts.

I also removed the battery control module, and opened it, it looked ok, but obviously you can't always tell by just looking at a circuit board if it's bad or not.

I'm not exactly sure what's going on here, if the battery control computer has gone bad, the battery itself, or something else in the battery circuit causing an issue.

I did take screen shots of the tech stream battery live data if anyone thinks they can help but needs a bit more than I've provided.

Thank you in advance for any help I get, I've solved a good number of problems with this car mostly from reading forums, but this one has me puzzled a bit.

 

Sorry, forgot to mention, it's a 2003 Prius.

 

Thanks for the response, lots of great pointers for me.

I'm guessing you're saying I should read each cell with my multi meter for resistance? Is that correct?

the inside resistance on tech stream from units 1 to 9 all read about 0.020 ohm if that's what you are referring to.

I did see where some guy on YouTube tested the wiring to the battery in resistances on each line, I'm sorry to say I got kind of lazy and just checked continuity on each line but didn't actually check to make sure the resistance is proper, I'll open it and check that again properly tomorrow. This is what I get for not just doing it right the first time.

 

I'll look again, the first time I opened the battery I didn't find any leaks on any cells.

While the battery is apart I guess I should load test the cells and see if I can identify any bad ones.

 

So I opened the battery again and looked for the blue ooze electrolyte leak, I had to look real close, but eventually saw hair thin lines of electrolyte all over the battery, I never would have even known they were there unless I was to put my eyeball's inches away from the cells.

I'll be disassembling the battery today to try and figure out what exactly is happening.

 

I'm not 100% sure if this gives any clues to what's going on, but I took my multi meter and set it to dc voltage, then I connected one probe to the metal internal metal case with an alligator clip, then I hooked up a probe to the other plug on the multi meter and I proceeded to probe the posts on the battery cells (bus bar and all battery plugs fully removed) and I received voltage readings on the posts that varied randomly from cell to cell starting at around .2 mv all the way to some cells reading up to around 7.5 v

I'm kind of thinking that sounds bad.

 

Hmm, my experiment of measuring voltage across the battery case and the cell posts appears to be flawed and basically worthless, I thought it would be much like measuring across two battery terminals, but I get different readings of each end of the cell battery posts. Oh well, at least I know those readings don't mean much now.

 

Ok, I have all of the cells out of the battery, labeled in the position and directions they came out.

I guess I'm going to try and load test them next with the 2 amp light bulb and multi meter method.

I'm not exactly sure how to go about checking to see if each cell is leaky or not, any advice would be greatly appreciated, all I know is their is real small amounts of the electrolytes all over the cells, but a person has to look real close to see it.

 

All batteries load tested correct at around 7.6 volts each holding for about 5 seconds each.

I'm starting to wonder if the problem is with the battery control computer or another component in the battery case.

wish I knew how to check the batteries for leakage, that would help out immensely.

 

From what I understand it turns out my experiment was almost the correct thing to do.

from my understanding you should measure the batteries out of circuit with a multi meter set on dc volts from the negative post to the bottom of the batteries metal nut holes, you will be looking for almost no voltage if the battery is not leaky, but if it is for sure leaky it will read close to full voltage.

6 of my batteries showed like around 5 volts, obviously bad.

7 of my batteries came in around a volt or a half volt, I'll change them as well because I don't trust them.

I'm posting this so if anyone has this same annoying problem and wonders across this thread it might help them out.

I'll post an update after I get my replacement batteries and test out my car to see if the triangle of death does indeed go away.

 

Thanks guy for steering me in the direction of leaky cells, I do believe your hunch will be correct.

 

The update.

Replacing the leaky cells that I diagnosed with my multimeter seems to have worked, the car was on for around 20 minutes without seeing the red triangle of death come on, it used to come on within about a minute.

I was discouraged however, after tearing the battery down, getting new cells, balancing all of my battery, and going through the mind numbing task of reassembling the battery, when I turned the car on the triangle came back, so I hooked up tech stream and read the codes, same as before I fixed the battery, so out of curiosity I reset the codes and to my surprise the codes stayed off.

My computers must have kept the codes stored which kind of puzzles me a bit, I had the 12 volt battery unplugged for a couple days, so I guess that always doesn't work to reset codes.

If anyone else finds themselves facing this problem try resetting the codes with tech stream, from what I see I needed to reset my codes as just unplugging the 12 volt wasn't enough.