Hi all, I have a 2008 FEH with about 250k miles on it. this summer when it was really hot it twice gave the "stop safely now" message and didn't want to start. I noticed the first time the HV battery was really hot so I stuck a bag of ice (in a thick plastic bag so no leaks) on it and then it started after about an hour and ran fine afterwards but had a code P1A10. the second time was a couple weeks later; this one we had to wait a couple of hours before it started. we drove it to the shop and it threw P1A10, PO562, U2511, B1016, POA27, POA7E, PO535 AND POA81. his scanner read the HV battery temp as -40. I found that the cooling fans work (can feel the air flow under the panel next to the battery) so it's not that, I guess. the shop guy said it might be the battery temp sensor, but after he cleared all of the codes and test drove it none of them came back.

I just got a scangauge3 and hooked that up tonight; the car has been sitting for a couple of weeks but it's not particularly hot right now (80 or 90). some of the odd readings I got were as follows: max battery module temp change = 39.2, ave battery module temp = -40, min battery module temp = 78.8, state of charge = -48.1 (fluctuates btw 48 and 49), traction battery temp = 0, traction battery voltage = 365. it does not throw any codes right now and ambient temp is about 77 or 78, and all these readings were in the driveway with the engine running (it did not go into EV mode, fwiw).

do these numbers mean I need a new battery temp sensor? and/or a new battery or do I just need to drive it around for a couple of hours to charge it up? my daughter wants the car at college which is 5 hours away; I guess that might charge it up, lol.

TIA, if there are any other data you want/need I can get that.
nik

 

Likely a failed sensor, wire or computer INSIDE the battery.

48-49% is a fine working SoC. At 365V, you don't need to charge it at all.

I currently own 8 hybrids, and I have sold 4. I fix Prius batteries. and have seen literally hundreds of hybrid failures. I would NEVER endorse sending a kid 5 hours away to college in a 10+ year old hybrid unless it had already experienced the typical failures and were replaced with new, e.g., for a Prius, HV battery, ABS actuator and inverter coolant pump.

 

so the (-) in front of the 48% SoC is nothing to worry about? it's my first scan with this unit, lol.
are the temp sensors difficult to replace? I'm a solid intermediate level mechanic, but better with older cars, lol
thanks!!

 

You're using a scangauge. I regard them as inferior to most OBDII bluetooth options.

Get Forscan.

 

I got a forscan, and it's telling me the average SoC is 83.96 and minimum was 52%. voltage was 325 today. my wife drove it about 15 miles earlier today and she said it did go into stealth mode (electric). it was going into electric in the driveway too while I was doing the scan. it was giving me a POA81 code again though. I stuck my hand in the battery air filter spot and could feel air flow but it wasn't air conditioned air-- felt like outside air (cool but not hot). still -40C for the evap temp on the scanner.
are there any other parameters I can use to see if the battery is overheating and why? Is there supposed to be AC air blowing back there onto the battery? the mechanic did replace the AC compressor 2 years ago and then had to re fix it this past summer because (he said) something was loose and grounding out. he says now that since the cabin AC works the battery AC shouldn't be affected. apparently he misplaced my battery air filter too so I have to find a new one of those too

 

if the blend door is open, the car is not cooling the battery with rear A/C.

P0A81 indicates one of the cooling fans isn't running.