Post-crash power loss on climb - regen/HV battery issue?

I recently got my 2007Prius back from the body shop after a 13k repair following a crash that crumpled my front end. The car seemed to be doing fine, until a long, steep climb had the battery drop to one bar, speed dropping to 40 despite a floored accelerator, and a red triangle that appeared briefly before disappearing just as we completed the climb. It's the dropping speed despite a floored accelerator and the warning light that have me worried.

I've driven that hill frequently with no issues -- in fact, climbed the same hill the day before, and the other side of that hill with no problems later the following day. I had taken my Scangauge off while the car was in the shop; I put it back on after getting home from the hill trip, and it reported no errors.

I'm not sure what to suspect, or what to do next. My issue was quite similar to the one summarized in this recent post:
http://priuschat.com/forums/gen-ii-prius-main-forum/95641-power-loss-low-battery-during-climb.html . . . with some important differences: I did get a red error light, my loss of battery bars and general thrust was not "sudden," and my issue closely followed a major crash and repair.

Haven't been up a major hill since (the hill in question is a distance away, we were heading on vacation) and have experienced no similar situations. Subjectively, it feels like maybe around town and on the freeway the Prius has a little less power, doesn't regen as much, gas mileage seems average or maybe a bit below, but I can't really say that for certain. (I had a non-hybrid rental with my Prius was in the shop for two weeks that went VROOM pretty easily, and may have skewed my perceptions).

Browsing further, especially on this thread of common problems, I ruled out the battery vent issue (it was and is unblocked), probably ruled out the inverter coolant pump issue because I did not get a concurrent VSC light with the red ! light ( I don't think so, anyway, I was pretty freaked out and focused on my MFD and that red light!). I did perform the DIY 12v battery test from this thread and get some slightly low readings: 12.3 average for the unloaded battery (healthy range 12.4-12.8), 11.9 for a loaded battery (12.0 healthy minimum), and 14.3 for a charging battery (13.6-14.4 healthy range). I did some easy stuff myself: changed the air filter, checked tire pressure, etc.

My first impulse was to get my HV battery, regen brakes, and ECU (the power was, apparently down at some point -- kept my memorizes NAV points but the annoying MFD/reverse beeps are back) checked by a Prius tech, but I don't really want to pay out of pocket for that (or even whether those are the likely culprits). At the same time, I don't want to take it back to the body shop without a clear idea of what's wrong.

My options, I think, are:
- replace the 12v battery, but I don't really know if my readings suggest real trouble there
- have a Prius tech check the car out, out-of-pocket
- take it back to the body shop with a vague descriptive complaint, and hope they agree to try and find something, and are competent at that
- try and figure out how to track HV battery current and block voltages (another issue discussed in the common problems thread above)
- something else that somebody on here recommends (I am an avid Prius owner and DIY as much as I can, though I am the farthest thing from a "car guy" or engineer).
- drive up a nearby really big hill and try and replicate the problem (which I'm avoiding, but we do have another mountain trip in August, with even harsher grades).

Any help appreciated.

thanks

doug

 

Thanks for the feedback, been checking through as many of these as I can today:

It's not low on oil; unsurprisingly they overfilled it My Scangauge, as far as I can tell, will measure only voltage. Running/ready, it reads 13.9-14.0; engine off, it reads 11.9-12.2. Didn't have the AC on during the climb.

Sounds like I need to recharge the battery, though .I'm trying to track down a friend of mine to borrow a battery charger; found a thread here on how to do it for a Gen II Prius.

 

I have not had the LSC done, but I did not get an error code, nor (I think) did the VSC and brake lights go on during the power loss, which seems to be the signature of an inverter pump failure. The reservoir is full and, when I run the ICE, churns and bubbles a little. Is that sufficient to show that the pump is working? It might just be the percussion of the ICE shaking the reservoir, but there are bubbles -- I'm just not sure if I'd say it's gurgling.

The radiator looks low; in fact (it's hard to see with that apron in the way) I can't see fluid in it at all. If in fact they didn't bleed the radiator and therefore the fluid is low, then this would go along with seilerts' diagnosis of the problem -- the car may have been just at the limit of overheating.

The only thing that makes me suspect that this isn't the key is that we got the warning light on a foggy morning; on the return trip up the same hill at over 80 degrees, the car did just fine.

It seems like what I need to do is take the car back to the body shop and have them top off the coolant (if they forgot to bleed the air, is this sufficient now that the air has, I think, cycled out, or do I need to require them to do a complete flush?)

I also will recharge the battery.

Any suggestions on how to further determine the fitness of the inverter pump?

Thank you for responding and tolerating my lack of automotive knowledge!

doug

 

I was able to see turbulence in the inverter system (bubbles looking into the reservoir in the top, and feeling movement in the tube leading up to it) AND hear the pump (I think, it was a pleasant pump-like sound right underneath the inverter fluid container) in non-ICE "ready" mode.

Also charged the battery with a really nice charger my friend borrowed from a university MechE lab, so that should do the trick.

Since I'm determined to do the LSC, we filled the radiator with generic antifreeze/water for the short-term-- it needed more than a quart.

Unfortunately, we did this before reading andyprius's post. When I get the LSC done, should I just have them bleed the radiator, and drain and fill the coolant? Is that the only way to be sure that system is 100%, air out, etc.?

I am taking the Prius up a local steep hill tomorrow unless anyone thinks that's a dangerous idea

 

Car made it up a five mile grade twice in the heat with all loads running (A/C maxed, stereo, headlights, okay not wipers) and never dropped below three bars on the HV battery. Looks good.

I have two last questions:

1) About a quart of what's in the radiator is what I put in (generic antifreeze and water) -- the level is fine now; is it important hat I go to the body shop and have them drain and fill it (and bleed it, not knowing if that's why the level was low last time)?

Also, the 12v battery readings have me confused, especially since the MFD and Scangauge are giving different readings (at literally the same time -- sorry, can't format this "chart").

ACC Mode/IG-ON/READY
Scan gauge 11.8 / 11.6 / 13.9
MFD 12.2 / 11.9 / 14.3

Scangauge shows 13.7 constantly when driving the vehicle.

2) Is this a 12v battery that needs to be replaced?

thanks

doug

 

The volt meter that was on the pretty high-end battery charger gave readings (pre-charge) that were higher than the MFD or the Scangauge -- it indicated that the battery didn't need recharging, though we did some anyway. So I guess my three readings of the battery show healthy/borderline/replacement . . . a tough call. Does it make sense to monitor the battery over time and when it starts to lose charge, even a bit, replace it in 6 mo/a year? Normally I am pro-preventive (or, in this case, pre-emptive maintenance). Still, I want to replace my battery only once, and I'm hoping to drive long enough that I want to wait as long as is reasonable before going over to the Optima battery.

Regarding the radiator and its contents at the moment -- having Toyota check (and, perhaps, drain, fill, and replace the fluid, etc.) it when I have the LSC done would, I assume, be an extra expense. Instead, should I take it back to the body shop which just replaced the radiator, but apparently misfilled it (didn't bleed it would be my guess) and lobby them to repair it without cost, but risk them screwing it up again?

I realize these are increasingly subjective questions, but I appreciate any input.

doug

 

Dropping the car off at the body shop tomorrow, they admit fault and will provide (ick!) a rental. Ordered an Optima battery and hopefully . . . that will be the end of it.

thanks folks

doug