HV Battery code P3000-389

I have a 2008 Prius with 280K on the original HV battery. The 12V battery was replaced three years ago. My son used it regularly until he went to college this year and then it really didn’t get used much. The last time it moved was in mid-March; he drove it a lot then, including a 5 hour road trip. When I went to check on it recently, it was dark. No lights or response on the dash when I pressed the power button. I tried attaching a booster pack without luck and then I tried the standard jump start from the relay box. I don’t recall now what happened, but it didn’t start. I pulled the 36 month old Toyota battery (12V) and charged it at 2A for 10 hours, but the voltage didn’t hold at 12.4V for very long. I then tied in another 12V battery so that the onboard screen showed 12.6V. Basically, I get the red triangle and no READY light. I hooked up Techstream and pulled the codes. Once I reset the battery and deleted old codes, what remains is P3000 (with the 389 sub/INF code for Battery Control System/abnormal signal from battery ECU) and two, likely related, codes in the chassis under the ABS/VSC/TRAC system: C1259 (HV System Regenerative Malfunction) and C1310 (HV System Malfunction).

When I reset the P3000 code the red triangle disappears momentarily before coming back ten seconds later and “Problem” being shown on the MFD screen along with a red hybrid battery light (main) battery icon on the MFD.

So, there are indications pointing to a low voltage condition in the hybrid battery. I had planned to recondition the battery when that time came, but I’m wondering if I can do anything to “top it off” to get it running again so I can deal with it in the fall when I have more time to dedicate to it? I have read about the THS charger at the dealer buying an additional 2% over 10 mins, but that doesn’t sound like much. Can it be run several times? Is there anything I can test to see how far out of tolerances the battery is from getting a Ready light and starting? Any suggestions before yanking the hybrid battery? I'd love to run it for the summer and monitor the hybrid battery with Dr. Prius app for the future rebuild if possible. Thanks in advance for any thoughts.

 

Tombukt2: I'd check the voltage but not sure where to do that. I suppose I can pull the seats and battery cover, but if there is an easier location . . . . Will Techstream show it anywhere? I was not able to locate the 14 battery packs in TS.

The "old" trouble codes looked like they were stored from earlier issues, but here is the full list:

P3000 Hybrid control Battery control system

C1241 ABS/VSC/TRAC Low battery positive voltage or abnormally high battery positive voltage
C1242 ABS/VSC/TRAC Open circuit in IG1/IG2 power source circuit
C1259 ABS/VSC/TRAC HV System regenerative malfunction
C1300 ABS/VSC/TRAC ABS ECU Malfunction
C1310 ABS/VSC/TRAC HV System Malfunction
C1378 ABS/VSC/TRAC Capacitor Communication Malfunction

B1421 Air Conditioner Solar sensor circuit (passenger side)
B1200 Gateway Body ECU communication stop
B1207 Gateway Smart Key ECU Communication Stop
B1271 Gateway Combination Meter ECU Communication Stop

 

I'll double check the codes tomorrow, but I don't recall any in the Battery ECU. The original scan included a full health check run on all 16 ECUs. Here are shots of the original health checks (2) and the freeze frame data from the P3000-389 code (1).

I have been looking at the grid charger route as a possible short term fix. Perhaps a few charge and discharge cycles would bring it back if this is the issue. I'll keep digging for the battery pack block voltages, but it certainly wasn't jumping out at me using Techstream ver. 15.0

 

Well, that’s interesting because it was at 208V the day before on Tuesday. If each cell is 7.6 then the total voltage would be 212.8, so when it was 208 it was only 2% low, and at 200V, is only 5% low. Toyota says that each engine start will drop the battery SOC 1% if I recall correctly. It doesn’t seem like that would be low enough to conk it out for starting. The shop manual recommends turning the crankshaft to verify it is free in the troubleshooting for the P3000-389 code. I’ll keep digging, but does 200V sound low enough to throw this code?

 

Went into the battery ECU and pulled the voltage data on the 14 blocks. All show a resistance of 0.019 ohms, but blocks 1 and 2 show voltages of 2.44V and 13.06v compared to the other twelve which are mostly around 15.00V (14.74v-15.00). Interesting that the end blocks are the lowest and the middle blocks the highest. I thought conventional wisdom was that the end blocks ran cooler and sustained higher voltages overall?

Anyway, I guess the next step would be to pull blocks 1 and 2 and test the four units? I'm guessing 1 and 2 are both bad in block 1 and maybe only one is bad in block 2? I'm all ears to suggestions for getting the car running again. Good suppliers? Best practice before just shoving 3-4 new cells in the old battery?

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Given that the voltage is currently around 200, and then one of the blocks is showing 2 V, that adding a new block (two purchased cells) should push the voltage up to 213V. And replacing block two would bump that up even more. How likely do you think it would be that doing this might get the battery into ready mode so that the car could be running again? I realize the new cells are not going to match the old ones very well, but it would seem to me that if they just were running again that things would begin to equalize, even if the ECU threw a few codes along the way during this process.

Perhaps running a grid charger to deep cycle the whole battery three times would help with this, although I don’t have one at the moment.

 

Wow. This is fantastic information. Like having a pair of eyes where I cannot see. I’ll get back to the car on Monday and pull the battery so I can get more accurate measurements. Thanks for everyone’s insight.

 

So, I pulled the 12V battery and the traction battery and disconnected the bus bars on the traction battery (which have a fair bit of corrosion on them). Incidentally, the voltage at the main terminals with the safety/service plug removed was still at 12V 30 minutes after pulling the plug. It was around 8 V after one hour. I was under the impression that the capacitors would fade after 5 minutes to 0 VDC so initially it had me scratching my head.

I then checked the initial voltages of all 28 modules:

Module # V
1 0.30
2 2.34
3 6.33
4 6.40
5 7.40
6 7.24
7 7.37
8 7.39
9 7.40
10 7.41
11 7.39
12 7.42
13 7.42
14 7.42
15 7.41
16 7.41
17 7.42
18 7.39
19 7.41
20 7.39
21 7.41
22 7.41
23 7.39
24 7.41
25 7.39
26 7.39
27 7.37
28 7.19

It would seem that modules 1 and 2 are toast. There is evidence of liquid/electrolyte staining on the pan of the battery tray. Modules 3 and 4 seem very low, as well. All of the other modules are in the 7.37-7.42 range except modules 6 and 28 which are 7.24 and 7.19, respectively. So, if I had all the hobby battery charging equipment, it might make sense to buy 4-6 modules and then go through all the reconditioning and determine if enough of these modules can be deep cycled and then balanced and placed back into service. But, I don't have that equipment. Anyone care to weight in on a reasonable course of action at this point? I'd love to be able to resurrect the car to let my son drive it through the summer and then maybe spend a bit more time on the battery then. I also called Green Bean and they are two weeks out for replacement batteries in California. I don't have much faith in their batteries, but I do like that I can buy a battery with a transferable lifetime warranty for $1624 plus tax.