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[AlanR]

I am losing power at full throttle so hoping the encoder alignment will sort it.
Bought the IXXAT 1.6 interface and made up an OBD2 lead.  Downloaded the old software but won't connect.
No data packets showing on the canbus.  Tried all speeds.
I put a scope on the can high and low pins and both just at 2.5v with no activity.
Plugged the interface into my car and straight away flashing light and plenty of data so the interface and software are working.
Is there something I need to do to access the sevcom canbus?  I can't see any info on turning on the ODB2 can messages.

If anyone needs the interface the seller I bought from as listed another on ebay for £150.  After a £100 offer I accepted a £120 counter offer.

[DerKrawallkeks]

I have accessed the Sevcon using DVT, but I spliced into the CAN cables directly. I didn't know (and still don't think so, please correct me) that the OBD2 plug on the Zero carried the CAN bus. As far as I knew, they just use the physical plug but they run UART (RX and TX wires) to it, and therefore don't stick to any OBD2 standard at all.
(Which might be cause OBD was invented for exhaust and emissions checking, which is not required and mandatory on an EV)
So the only thing I can say works for sure is splicing into the CAN wires coming from the sevcon. Don't forget the CAN gnd.

[AlanR]

Thanks.  There is a CAN bus on it.  On the diagram it goes straight to MBB2.  I have cleared a fault using it before and I would guess it must be possible to use it when servicing to align the encoder.  Maybe sending the right command to the UART it will connect this to the Sevcon CAN bus.

[karlh]

Alan,

UARTs work with serial busses (RS232), not CAN.  There is a UART-CAN-Protocol available, but it's not yet finalized.

I'm not sure about your 2021 model, but the 2020 DS has both CAN (pins 6 and 14) and serial (pins 8 and 9) connections to the MBB through the data link connector.

[AlanR]

I understand Karl.  The 2016 diagram on zeromanual.com shows the same at yours.
I meant maybe a serial command can be sent to the MBB to allow the Sevcon controller to be accessed over the OBD CAN bus.  Or possibly a CAN command to do the same.  As in some kind of service mode.  I would assume that Zero dealers must do this to carry out the "motor commissioning" with the DVT software.

[karlh]

Looking at the 2020 schematics I have access to, I don't see where the Sevcon is on either the CAN or serial busses.

[rgutt]

I have a 2021 SR, which should be pretty much electrically identical to your DS except that I have 2 OBDII plugs, only one of which has access to the CANbus that ultimately connects to the Sevcon. Just FYI, the one that provides access to the CANbus on my bike is the one not labeled as OBDII. Sitting on the bike, it's the plug on the left. On that plug, the pins you need are 6 (CAN high), 11 (CAN ground), and 14 (CAN low), and I think the speed is 500kbps.

To some of the other posts, the Sevcon is absolutely on the CANbus. Zero is constantly writing the max battery discharge rates to it. It also uses the SDS protocol to switch between the riding modes. And speed information ultimately originates only from the Sevcon. The MBB might retransmit it in a different format for the dash.

[AlanR]

I found that I had another unmarked ODB2 style plug too.  I could connect to the sevcon through it.
I noticed the angle was showing as 0° so maybe this setting got lost.  It seems strange the bike was working perfectly but after a week at home while I was on holiday it started misbehaving.
I can adjust the angle through it fine but my software didn't seem to have an option to run the motor and get the plot to work out the angle correction.
I tried using the throttle with limited success.  I seem to have wiped some settings trying and now the contactor won't engage.
Looks like I need to make a 200 mile round trip to the dealer to drop off and another to collect which is what I was trying to avoid in the first place.

[rgutt]

Hopefully, you just put your controller into pre-op mode. You have to put it back into Operational and cycle the key for the contactor to close again.

As for setting your encoder angle, from the PMAC encoder setup screen, click "Graph Uq/Ud vectors from no torque coast down trace" to pull up a graph while you manually rotate the rear wheel. The pattern of dots should center around due north. Adjust the offset angle until they do.

[AlanR]

Thanks rgutt.  I wish I'd known I could just rotate by hand.  Too late now though.
I need to wait 2 weeks before the Zero dealer can look at it.
It is in operational.
What I did was select torque mode and it asked to load default values and I selected yes.  I don't think is has wiped all settings from the sevcon.  There are lots of speeds ant voltages that look like they could be correct.  I can't see how it controls the contactor.  Can anyone describe this?  There is one digital output set for the contactor.  I tried adding 3 in case that was wiped but makes no difference.
If anyone can send me their settings or screenshots it would be greatly appreciated.

[DerKrawallkeks]

Hey,
here's roughly what I have in my bike. It's not my actual bike but a different Sevcon inverter flashed with my DCF, but the settings are all the same, since it is my bike's DCF.
Hope it helps some. This is a 2013 though (with software update around 2016). So if yours is configured differently, that doesn't indicate anything really

[atomicdog]

There are three separate CAN busses (OBDII, Powertrain, Dash/misc).
The one on the OBDII connector isn't directly connected to the Sevcon.

[rgutt]

Thanks rgutt.  I wish I'd known I could just rotate by hand.  Too late now though.
I need to wait 2 weeks before the Zero dealer can look at it.
It is in operational.
What I did was select torque mode and it asked to load default values and I selected yes.  I don't think is has wiped all settings from the sevcon.  There are lots of speeds ant voltages that look like they could be correct.  I can't see how it controls the contactor.  Can anyone describe this?  There is one digital output set for the contactor.  I tried adding 3 in case that was wiped but makes no difference.
If anyone can send me their settings or screenshots it would be greatly appreciated.

I have no idea what values the program throws if you select to load defaults. A lot of the parameters in the DCF pertain to the motor tuning parameters, which very well could be made on a motor-by-motor basis. As for the signal for closing the contactor, it originates from a TPDO on the Sevcon. The sevcon transmits 116 on bytes 7 and 8 of COB-ID 0x00000501.

I tried to attach my backup DCF, but it's apparently just over the website's size limit. If you message me you email, I can send it to you. I strongly recommend making a backup of what you've got even though yours isn't running at the moment.

[AlanR]

Hey,
here's roughly what I have in my bike. It's not my actual bike but a different Sevcon inverter flashed with my DCF, but the settings are all the same, since it is my bike's DCF.
Hope it helps some. This is a 2013 though (with software update around 2016). So if yours is configured differently, that doesn't indicate anything really

Thanks.  I have found a few problems particularly with the inputs.  A lot of the settings seem ok.  Still not working though.

[DerKrawallkeks]

Are you getting any faults? (my guess is no, cause you say you are operational..?)