Dax
Posts: 3
Joined: Tue Jun 04, 2013 9:47 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Fri Jun 21, 2013 7:14 am

Hi,

@cristi:
- what happens if we leave the OBDLink connected to the car for a long time (e.g. overnight, with the car standing still)? Is there a secondary battery that may drain?
- Is the OBD connector powered when the "ignition" key is off (I can't test this now since we have the car for limited amounts of time but I vaguely remember that it does so).

There is a 12-volt lead-acid battery that is charged from the tractionbattery and the OBD2 Pin 16 should be directly connected to the second battery (not sure if the OBD2 specifaction regualtes that). So there is allways a ~12V current (unsafe source [ger]). So if you connect a consumer to it, the lead-acid battery should drain. Maybe it is charged by the tractionbattery even if the car is off. To avoid that you could use a relais, that has your interface connected as your load circuit and the radio or something else that works with igniion on only as your controll circuit.

Best regards,
Dax

cristi
Posts: 11
Joined: Thu May 23, 2013 6:52 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Sat Jun 22, 2013 2:48 am

Thanks!

The STN11xx circuit has PowerSave functionality, so if this turns out to be an issue, I will look into that. Nobody wants to drain the auxiliary as it drives the charging for the traction battery...

According to iMiEV wikipedia the auxiliary battery "is charged from the main traction battery via a DC-DC voltage reduction device".

Also I would guess that the OBD2 adapter (of whatever sort) will take around 0.1 Amps, that's 1,2 watt (much less than the car radio), which seems very little for a car battery with tens of Ah, let alone one that can charge from a much larger battery, which in turn is connected to the mains quite often.

So as I see it (maybe I'm wrong) this is no problem, but I was wondering if anybody has any practical experience with keeping an OBD2 adapter connected for a long time.

best, cristi

Dax
Posts: 3
Joined: Tue Jun 04, 2013 9:47 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Sat Jun 22, 2013 5:16 am

Hi,

I think this could is a problem, because it is weighting your measurement results that are related to the battery. Only if the car is parked without charging for a long time ;)

Dax

cristi
Posts: 11
Joined: Thu May 23, 2013 6:52 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Sat Jul 06, 2013 8:45 pm

Hello

Does anybody have experience (and maybe a CAN log) from a car charging? In particular, is there any way to find out anything about the charging progress?

I remember that there is much less data on the bus when the ignition key is not turned, and probably there is even less when the key is not present.

But any clue about the charging progress would be very valuable to have. If anybody has a charging-car log, I will gladly help on analyzing it.

Thanks!

cristi

svingen
Posts: 8
Joined: Thu May 01, 2014 1:39 pm

Re: Decyphering iMiEV and iON CAR-CAN message data

Thu May 01, 2014 1:42 pm

does any one have try to get the can message when you use the remote controll to start the heater? (climate controls)?
would be great to get this implemented in OVMS :)

so can start the climate any where from (using OVMS)

if the message can be capture and then use OVMS to send it again to start the heater.

cristi
Posts: 11
Joined: Thu May 23, 2013 6:52 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Mon May 05, 2014 9:14 am

We are also very interested in climate control PIDs. We drew some logs with the car standing still, moving the climate control knobs to various positions, but don't have much experience in analyzing logs. Can anyone help?

svingen
Posts: 8
Joined: Thu May 01, 2014 1:39 pm

Re: Decyphering iMiEV and iON CAR-CAN message data

Tue May 06, 2014 1:00 am

cristi wrote:We are also very interested in climate control PIDs. We drew some logs with the car standing still, moving the climate control knobs to various positions, but don't have much experience in analyzing logs. Can anyone help?


i`am not a exspert but if you post the log mabey we can find it out? and mabey a smart dude read this and can help :)

do you have the remote to start the heater also?

cristi
Posts: 11
Joined: Thu May 23, 2013 6:52 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Tue May 06, 2014 4:38 pm

svingen wrote:i`am not a exspert but if you post the log mabey we can find it out? and mabey a smart dude read this and can help :)

here is the log:
http://ev.csc.kth.se/cristi/stn_simulator/logs/heating.txt

77 seconds into the log you can see the range (PID 346 byte 7) dropping from 42 to 30 hex due to turning the heating on.

"3/20/2014 11:02:50 AM",3462710572000000042
...

"3/20/2014 11:02:51 AM",3462710572000000030

Then the range keeps varying as we played with heating and ventilation...

I am trying to find PIDs that change in correlation with these events, I only suspect 3A4 and 384

svingen wrote:do you have the remote to start the heater also?

unfortunately not.

priusfan
Posts: 194
Joined: Mon Oct 08, 2012 7:39 am
Location: France

Re: Decyphering iMiEV and iON CAR-CAN message data

Wed May 14, 2014 12:48 am

Bonjour
@Cristi
I analysed your log.
In my opinion, in this log, you played only with the airconditioner, not with the heating...

I sent you a PM, please contact me...

Xavier

cristi
Posts: 11
Joined: Thu May 23, 2013 6:52 am

Re: Decyphering iMiEV and iON CAR-CAN message data

Wed May 14, 2014 7:24 am

Bonjour Priusfan, thanks for your message and for the log analysis,

We finally realized that PID 3A4 represents the climate control dials.

byte 0 represents the position of the heating/cooling (top) dial (the 4 least significant bits). It is 7 when heating/cooling is off, <7 means cooling, >7 means heating. More significant bits indicate AC on, heating MAX on, air recirculation on (i.e. pushing the 3 dials)

byte 1 represents the position of the ventilation (middle) dial, its 4 least significant bits are the dial position. The most significant bit(s) represent defrost, etc.

On PID 384 that you indicated we see the _effects_ of these dials. Byte 4 is the heating current multiplied with 10 and varies quite a lot (ramps up slowly when the heating + ventilation are on, then it goes to zero again, then it goes up again regularly). We are interested in estimating the heating (and other factors) effect on range so 3A4 is what we were after.

Cheers, cristi

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