soc reset

[Ryan_C]

I ended up pulling the #16 fuse under the hood, it's a bigger fuse, not one of the mini ones. I checked out the manual that is available for download and it mentioned either #16 under hood or #18 under the dash. I still couldn't figure out which fuse was which under there unless I am missing a cover under the dash or something.

Thanks for the help. I will probably pick up a "soc reset" switch in the future some time.

[Willie Williford]

Fuse function and location is printed on the back of the fold out tray/ cubby hole door. IIRR.

Willie

[eq1]

Originally Posted by thedhgroup

.... I have my charger set to 169v. I think if it sees 168 or more for 2 minutes it does a positive recal. (on mine anyway)....I have an 8amp charger up to 165v then a 700ma charger to take it to 169. So it only takes me an hour to charge it back up. (if it is not super hot out - then I just don't charge)....

What you do defies my understanding of the battery and charging. Maybe you're not trying to fully charge the battery? Correct me if I'm wrong, but in general people do try to charge the battery to full with grid charging, and that takes a higher voltage than 169V; I thought it was about 177V, such as 'set the grid charger to 177V unloaded'? Using the car's system I can consistently charge up to 168V. I've seen 170V at very low input amps, less than 2 amps, maybe as low as 0.3 amps... I assume this isn't full, but rather, what Honda determined to be about 75% SoC. What voltage does a fully charged battery settle at after a grid charge, after maybe an hour or two?

When I cycled my sticks, average voltage at delta V was 9.2V at 5.5 amps. That's 184 volts for the whole pack. Not sure what it settled down to though, after some time...

[thedhgroup]

Originally Posted by eq1

What you do defies my understanding of the battery and charging. Maybe you're not trying to fully charge the battery?

Correct, about once every 3 months or so (or if I get a premature negative recal) I then charge at a higher voltage and watch the battery temp very closely.

Back to SOC reset, if your voltage is over 168 and you turn your ignition ahead (engine not running) What happens after about 2 minutes? On mine it does a positive recal. On my Accord Hybrid it does a positive recal at 170.

The next time I have the battery compartment open I plan on tapping into the BCM so it can be powered while charging. This way it can keep track of the amps in. Thus eliminating the 2 minute wait or the annoying background charge.

I've never pulled fuses or the negative battery connection. (maybe my BCM is an old version?)

[Rush]

Originally Posted by thedhgroup

The next time I have the battery compartment open I plan on tapping into the BCM so it can be powered while charging. This way it can keep track of the amps in. Thus eliminating the 2 minute wait or the annoying background charge.

I must have missed this, could you explain in more detail what happens and what wires are tapped into and what PCB or circuit is used? Who came up with this?
Thanks

[diamondlarry]

Originally Posted by thedhgroup

Correct, about once every 3 months or so (or if I get a premature negative recal) I then charge at a higher voltage and watch the battery temp very closely.

Back to SOC reset, if your voltage is over 168 and you turn your ignition ahead (engine not running) What happens after about 2 minutes? On mine it does a positive recal. On my Accord Hybrid it does a positive recal at 170.

The next time I have the battery compartment open I plan on tapping into the BCM so it can be powered while charging. This way it can keep track of the amps in. Thus eliminating the 2 minute wait or the annoying background charge.

I've never pulled fuses or the negative battery connection. (maybe my BCM is an old version?)

This is one of the biggest reasons I like my "dumb(read:cheap)" charger because all I have to do is leave the ignition on and hook up a cheap 12V charger with a 10-15 amp output that will cycle back to a 2A level. Total cost for both chargers is ~$250(even less if I'd built the grid-charger myself) vs ~$850 for one that is, admittedly more sophisticated, but won't/can't do what I want it to do.

[thedhgroup]

Originally Posted by Rush

I must have missed this, could you explain in more detail what happens and what wires are tapped into and what PCB or circuit is used? Who came up with this?
Thanks

I first read about it here:

Wiring BCM to Power with RS-25-12 - how?

But there is talk in that thread about the fact the 12V power supply to do so would also have to be grounded which makes sense but also may be a safety issue.

In that thread there is a video that uhtrinity made showing a positive recal with ignition ahead:

100_0888.MOV - YouTube

100_0888.MOV - YouTube

[Rush]

Originally Posted by thedhgroup

I first read about it here:

Wiring BCM to Power with RS-25-12 - how?

But there is talk in that thread about the fact the 12V power supply to do so would also have to be grounded which makes sense but also may be a safety issue.

In that thread there is a video that uhtrinity made showing a positive recal with ignition ahead:

100_0888.MOV - YouTube

I'm not sure that I would do that, Mike D seems to think that there is a potential for problems...

"Trying to power up the BCM and MCM without any of the other circuits that connect to them being powered, may not be a good idea, and adds a lot of complexity and potential risk when doing grid charging.
I would not recommend going down that route. What is the big deal about a positive recal?" Mike D - Post #14 from same thread

[Eli]

Rush, there are several people who have done this. It works fine. I always planned on it, but it was easier to just do what diamondlarry says and leave the car on with a 12V charger hooked up.

It's pretty much a novelty, though there is probably some real value in having the SoC read 100.0%.

That BCM Gauge video is very old with a very early version of the software, the BCM never reads 100% like that normally unless grid charged.

Picture taken at 1:42PM, a bit after the grid charge was started:


This was taken at 5:12PM:


So it took 3 hours and 30 minutes for the SoC to move by ~16% @ ~350mA, or ~76.5mAh/percent. Interesting.

[Rush]

Ok, Didn't know that, thanks for setting me straight.

So then the 100% means 100% of *whatever Honda has decided that the max usable is*, correct? Is that also the same for 90%, 80%, etc.? Confusing... Now we have to specify what SOC definition we are using, right?