IMA/CEL Options

[thinman]

Gents - you have all been most helpful and generous with time and advice. Will be doing the IMA reset and do a rev charge today since I don't have a road trip in my future and don't give it enough exercise on a regular basis (as seems to be a contributing factor in this issue). Will also be looking into grid charger, particularly if there is a local (Seattle area) techie that can give me a hand with the harness.

[thinman]

Some Results - OK, I did the IMA reset and ran the car (on the road to do some errands) at hi rps. I got to positive recal within about 2 miles and the bars maxed out. I had a small hill and parked for an errand to find on return that I was at about 1/2 on the regen. I did some more hi-rpm driving to get the regen bars back up. Parked for another errand and the bars did not drop so much. Driving home, did some more hi-rpm driving and topped up the bars in the drive (total of about 10 miles). Let's see how the charge looks tomorrow. Thanks again to all for the advice.

[eq1]

I need a few clarifications:

Originally Posted by thinman

Some Results - OK, I did the IMA reset and ran the car (on the road to do some errands) at hi rps.

RPMs, right?.

Originally Posted by thinman

I got to positive recal within about 2 miles and the bars maxed out. I had a small hill and parked for an errand to find on return that I was at about 1/2 on the regen.

I presume you're talking about state of charge, SoC, rather than the charge/regen gauge. Did the SoC gauge bars really max out, or was it 19 bars? When you came back to the car the SoC gauge was back down to half?? I've never seen any movement after parking, let alone that extreme movement, though one or two people recently said they've lost a bar or two while being parked...

Originally Posted by thinman

I did some more hi-rpm driving to get the regen bars back up. Parked for another errand and the bars did not drop so much. Driving home, did some more hi-rpm driving and topped up the bars in the drive (total of about 10 miles).

So, when you say "high rpm driving," I take it that the IMA is in forced charge mode? - during which higher rpms tend to allow more charging... Is your normal assist and regen disabled? As far as I know, just driving at high rpms under normal conditions doesn't charge the HV batt anymore than at other times... If your battery's low you might get a background charge during which the IMA scavenges power from the ICE when you're say cruising on the freeway, or you have the rpms up around 2000+ and are being light on the throttle. But excessively high rpms do nothing extra in this case...

I guess, what's mainly throwing me off is that you say you had a positive recal, which to me means the battery's charged up, but then you're talking about behaviors associated with an uncharged battery... Not that that isn't possible; I've just never seen it...

[thinman]

Originally Posted by eq1

I need a few clarifications:



RPMs, right?.

Correct...



I presume you're talking about state of charge, SoC, rather than the charge/regen gauge. Did the SoC gauge bars really max out, or was it 19 bars? When you came back to the car the SoC gauge was back down to half?? I've never seen any movement after parking, let alone that extreme movement, though one or two people recently said they've lost a bar or two while being parked...

If SoC is the big gauge on the right, that's correct (new at the terminology). It looked like it was maxed but could have been 19 bars...will check more carefully next time. There was a drop to half, some due perhaps to doing a hill that I noticed before parking but definately some while it was parked for about 5 minutes.


So, when you say "high rpm driving," I take it that the IMA is in forced charge mode? - during which higher rpms tend to allow more charging... Is your normal assist and regen disabled? As far as I know, just driving at high rpms under normal conditions doesn't charge the HV batt anymore than at other times... If your battery's low you might get a background charge during which the IMA scavenges power from the ICE when you're say cruising on the freeway, or you have the rpms up around 2000+ and are being light on the throttle. But excessively high rpms do nothing extra in this case...

Yes - in a forced charge mode. Normal assist and regen has not been disabled. Reason for high rpm driving was to get some charging done without risking power steering fault. RPMs were over 3K to get extra charging effect. (I just kept in first gear.)

I guess, what's mainly throwing me off is that you say you had a positive recal, which to me means the battery's charged up, but then you're talking about behaviors associated with an uncharged battery... Not that that isn't possible; I've just never seen it...

Again a possible terminology issue....per thread above, I was at 3-4 bars, force charged for a little while after which the bars were being added every few seconds. Maybe that wasn't a positive recal after all. Can you amplify on this piece a bit more??

Update on results - had a full charge this morning when I headed out and had no drop in charge while parked for a couple hours. Heading back home, with one longish hill to climb, SoC bars started dropping pretty fast (below half) then to about 4 bars. I did some force charging in the driveway and SoC is back to about half but haven't done a full recharge. (I also managed to get an EPS light in the driveway.)

Question - what is the normal (or optimum) number of bars that should be seen on the SoC gauge??

Thanks again for talking me thru this. You all have been most helpful.

[eq1]

Sounds like you got a positive recal, yet I've never heard of a positive recal that will fall back to half the gauge without having used assist, such as parking the car and coming back to it some short time later...

If I were you I'd try to avoid assist until the SoC gauge seems firmly planted at 19 bars. A positive recal should take it up all the way to 19 bars - is that what happened initially? 19 bars is more or less the optimal, maybe 20. I suppose it doesn't matter that much with new batteries, but with old ones 19 bars leaves some headroom, while also keeping you a good ways above the point where background charging will automatically kick in... 20 bars is good too, just that if you're on the high end of the 20 bar charge level (like 76.1% to 81%, depends on ECM), the car will simply drain the battery back down to 19 bars automatically...