BMW i3 CCS/charge port controller

[EV_Builder]

Let's play spot the difference.

Type 1 CCS vs Type 2 CCS!!

[EV_Builder]

More experiments. Neither of my LIMs will do the weld test. But both report test passed. If I disconnect the contactors they report test passed. So off I went back to my ccs station with the contactors disconnected. Guess what? Fails in the exact same way. I can sit there in precharge until the station times out but the second I want contactors its night night. Almost as if the LIM can't see the contactors isn't it?

Now if you were a paranoid oem and worried about someone swapping a lim to repair an accident damaged car would you do something like disable the dc contactors if say the lim sees a different vin or no vin?

The last 7 digits of the vin are transmitted in 0x380. Good news is I have the Vin for the 2017 LIM. Hey that rymes. Do you have a vin for your lim? Let's see what happens. Probably another blind alley but it feeds my paranoia so that's never a bad thing.

If I where an OEM I would let them charge AC because else the car is useless. For FC DC i would suspect the car gives a warning so you don't try todo that. Until all errors are clear. Also AC charging doesn't need those relais.

Are both contactors equal? Not that it somehow knows that they are swapped. Voltage measurement vs relais output.. Else i suspect a difference in the setup, so would suggest a bigger and better comparison. Is the schematic of the small board in the video known?

Maybe this issue is as simple as that the Lim needs to be cleared from errors from the past...

[Jack Bauer]

Ok so regards errors on the stations. Ionity gives no error. Efacec qc45 helpfully says : DTC4341.

Regards talking to the LIM with BMW tools its not too hard in theory. I have all the software like ISTA+ ESYS etc and an ENET cable. Problem is in the i3 the obd port is routed through a module called the BDC (Body Domain Controller) as we can't have those pesky car hackers getting access to CAN!!! So to get fault codes, live data or code the module to a car we would need something like a BDC simulator or a bdc itself :
https://www.aliexpress.com/item/33028327644.html
Have one on the way just in case.

I suspect the VIN for our purposes is a red herring. If we were just swapping a lim into an accident damaged car then its a big deal as it will not work if it sees the incorrect vin in 0x380. Now what would be super fun is to use a can bridge in a working i3 to kill 0x380 to the lim and see if it will still fast charge. Sadly though I don't have 20k to go buy an i3 for experiments:)

Anyway, I do believe my lack of ability to perform the weld test and lack of contactor close during ccs are linked. If it will do one it will do the other. So I think its down to one of two things : Wrong/missing CAN messages , hardware setup. I'll keep going...

[EV_Builder]

Ok so regards errors on the stations. Ionity gives no error. Efacec qc45 helpfully says : DTC4341.

Regards talking to the LIM with BMW tools its not too hard in theory. I have all the software like ISTA+ ESYS etc and an ENET cable. Problem is in the i3 the obd port is routed through a module called the BDC (Body Domain Controller) as we can't have those pesky car hackers getting access to CAN!!! So to get fault codes, live data or code the module to a car we would need something like a BDC simulator or a bdc itself :
https://www.aliexpress.com/item/33028327644.html
Have one on the way just in case.

I suspect the VIN for our purposes is a red herring. If we were just swapping a lim into an accident damaged car then its a big deal as it will not work if it sees the incorrect vin in 0x380. Now what would be super fun is to use a can bridge in a working i3 to kill 0x380 to the lim and see if it will still fast charge. Sadly though I don't have 20k to go buy an i3 for experiments:)

Anyway, I do believe my lack of ability to perform the weld test and lack of contactor close during ccs are linked. If it will do one it will do the other. So I think its down to one of two things : Wrong/missing CAN messages , hardware setup. I'll keep going...

Is there an EEPROM on the PCB?

[EV_Builder]

i made a little video of the weldtest. At the top left is the battery voltage, at the top right is the voltage of the main contactors (measured by the ISA shunt). somewhere in the middle "DC Spannung am Stecker" is the voltage at the port (measured with my board). The last line shows the status of the DC contactors. The second from the right is nomaly OK. If I give a voltage on the port, it changes to unexpected DC on the port, after removing the voltage on the port it reports both contactors weldet. Now my code starts the diagnosis and the error is cleard.

on my testbuild the lower 3 LED are the RGB controled by te LIM (doesn't have a blue one), The upper two LEDs show the state of the DC contactors, simulatet by litle relais and 16 Ohm resistors.

Does it work if you omit 0x380?
Does it work after you send the wrong 0x380?
I guess that it will work after you send the correct 0x380..

[Jack Bauer]

No eeprom sadly! First thing I checked:)

[Jack Bauer]

You guys are gonna love this. Weld test now working on the bench with code posted above. No vins needed.
Genius here had the rely coils wired wrongly! I had one relay on both + and one on both -. Guess what? Its the same in the car. See, I warned you guys about leaving something as important as opensource ccs in the hands of a a moron. so it's really all your fault not mine...

Weld test will occur if
a) lim is started from cold, cp door is closed, ign turned on.
b)abnormal voltage detected on ccs pins, door closed, ign off then on.

[tom91]

This just proves that sometimes its good to take a step back and look at the basics.

Fingers crossed now it will get to the next step on the CCS charge session.

[EV_Builder]

As suspected, but nice to know this, good find! Leaves me with the question: how could it report firstly that it passed that test. You get the same result right now?!? DBC adjusted?

Though nut to crack.

[muehlpower]

Weld test will occur if
a) lim is started from cold, cp door is closed, ign turned on.
b)abnormal voltage detected on ccs pins, door closed, ign off then on.

and c) the link voltage on 112h must be above 200V!

[Jack Bauer]

Update : Car wiring changed. With 2014 LIM fitted we weld test on ign on as per the bench. 2017 LIM no weld test. Pulled both lims onto the bench. 2014 cold starts with a contactor fault and then weld tests at ign on. 2017 cold starts with no fault but will weld test if one is generated by putting an unexpected voltage on the ccs dc pins. going to refit the 2017 and go visit mr.ionity.

[cloudy]

The anticipation...!

[Jack Bauer]

We're charging:)

[mikeselectricstuff]

I love it when a plan comes together... can't wait for the video...

[Boxster EV]

Well played and great perseverance.

I’m on eBay now trying to find a LIM module.

[Bryson]

Epic!! Great work Damien

[tom91]

We're charging:)

Was it really that simple.

Great to see it was something so obvious and not VW trying to make your life hard.

[Jack Bauer]

Yeah pritty much. There is a bug in state 5 of my ccs state machine. I'll leave it there for you guys to find. Video soon.

So the LIM branch on the vcu wiki is what I used today. No vins or other nonsense required. Probably a lot of can messages on there that don't need to be. I'll camp out at a charger and chop off msgs until it stops working once the dust settles. In the meantime would super appreciate a bit of help to tidy things up in the LIM class and maybe give it a way to control current ramp, cv state etc and oh yeah a shutdown state would help:) Had to shutdown the session via the app which pissed the LIM off a bit. Interestingly it did a contactor weld test when I fired up the car to go home.

Now I'm off to fit my groovy ZeroEV rgb button to the charge port ....

[Jack Bauer]

Oh yeah and the session went on for 20 mins. I had to stop it as the car was full so the LIM must have been happy from a CAN point of view.

[MattsAwesomeStuff]

We're charging:)

[P.S.Mangelsdorf]

We're charging:)

Sounds like I need to remove the plain-jane J1772 port I just installed this weekend. Dammit Damien, now I'm doing upgrades before the car is even on the road!

Congrats, and once again thank you for your efforts!

[Jack Bauer]

Sorry guys. I really tried to screw it up...

[Isaac96]

Awesome. Ebay time! (Also I need to learn C for the controller).

[jon volk]

And just like that i3 Lim values soar.

[EV_Builder]

Coool!!! Very Cool!
So now we need the board to generate the special signal right?