CAN Wheel speeds from AIM dash to M150

[oversteer]

Hello

I'm trying to get can wheel speeds from a AIM MXS Strada 1.2(From a 2005 Subaru) to an M150, I have decipehered the the Subaru CAN messages and have all 4 wheel speeds displayed on dash, after a few math channels reading correctly.
I have set up CAN transmit in dash to use Big endian 11 bit ID 0x07F0 with 2 byte data..


When I set the ECU recieve on CAN2 with that ID I juust get message timeout when using CAN2 Offset 0,2,4 and 6.


Dash works receiving dash stream and a couple of custom transmits from M150 so I know that bus is fine in that direction, what am I doing wrong with the Dash to M150 !?

Cheers

[Stephen Dean]

Hi,

If you download the MoTeC Utilities from here, this will install CAN Inspector. Run CAN Inspector on the M! CAN buts to see if the messages are being transmitted and what what data is being transmitted if it is there. You can also save the logs and send then to support @ motec.com.au.

[oversteer]

Hi Stephen

I did look at the CAN data and can see the message 7F0 being transmitted... as I would expect it, but is this what the M150 wants ? (right click open image in new tab to see data, its all zeros as car is not moving.)


Motec CAN Inspector log
https://drive.google.com/file/d/1y0fp-7 ... sp=sharing

[David Ferguson]

Would you post your M1 Package. Your screen shots are cropped and I can't see all the information you are trying to show. Be sure to export your package so an archive file is created.

[oversteer]

Yes the pictures are getting cropped but if you open in new tab they are not, couldn't work out why and didn't want to go write BB code !

OK, below is a share of the tune, dash config and a can sniff.

https://drive.google.com/drive/folders/ ... sp=sharing

I have moved everything onto can1 on the M150 so I can have PDM data on dash, which is can1 on dash, can2 on dash is linked to subaru bus.

Cheers

[David Ferguson]

I think your issue is with the AiM system. The CAN log shows the data is always all zeros for data sent to CAN id 0x7F0.

Looking at your AiM config, the wheelspeed data is calculated via Math Functions from individual bytes (not sure why this can't be done in the protocol). If you could add the "Justin - Subaru Wheelspd 500 Kbit/sec CAN protocol, we could take a look.
I know you have a Strada (so no logging), but if you connect using Race Studio 3, and use the Live Measures function, do the calculated channels FLWS, FRWS, RLWS, RRWS update when the vehicle is moving?
If they don't then, do the channels from the CAN2 connection (FLWSB1, FLWSB2, etc) update? If not, then that is what you need to work on first.

Hope that helps.

[David Ferguson]

OK, just looked at your M1 Package. You have configured the Wheelspeed channels to look for address 0x7f1 by selecting "CAN 1 Offset xx". Change all of those to use "CAN 0 Offset xx". (easy way is Initial Setup->ECU I/O, search "wheel")

The M1 can receive data from 0x7f0 (CAN 0 offset xxx), to 0x7f7 (CAN 7 offset xxx), so you will be able to send additional sensor data if you wish.

[oversteer]

Hi David

Thanks for you assistance, the Dash does display the wheel speed correctly, the block of 4 11's are the individual wheels and the 11 middle bottom is the speed from the gearbox sensor, speeds track perfect 0-150Kmph.


This file is the CAN sniff of this being sent to M150 when I took the picture of the dash, its doing ;
00 0A 00 0A 00 0A 00 0B
https://drive.google.com/file/d/1j1KGA7 ... sp=sharing

This is the Subaru bus doing a run to ~40Kmph and back down, 513 is wheel speeds ;
https://drive.google.com/file/d/1lKDm65 ... sp=sharing

This is deciphered in excel, same math as being used in Dash ;
https://docs.google.com/spreadsheets/d/ ... ue&sd=true

The Subaru can data is the "2nd bit * 256 + first bit", then * 0.055555 to get Kmph, which is possibly backwards or different from what's normally expected !?

05 01 05 02 05 03 05 04 would be FL-15Kmph, FR-28.7Kmph, RL-42.9Kmph, RR-57.1Kmph

So I got the CAN resource wrong, I thought CAN 0 was bus 0, and CAN 1 was bus 1 !! anyway setting wheel speed to CAN 0 Offset 0 no longer shows red box with CAN TIMEOUT and an error, but it does state can timeout in diagnostic, and there isn't any speeds coming through !

M150 log file, not that it shows much, can't see how to log can data !?
https://drive.google.com/file/d/1LagEc5 ... sp=sharing

[David Ferguson]

What is expected is the frequency of the wheel pulses, this is then converted to speed using the pulses per revolution and the wheel circumference. I will look at your CAN captures and the M1 Package and provide a recommended change. We should just need to scale the data correctly.

[oversteer]

Ok, so it won't accept and intger as a speed !? How do I get dash to produce required pulse ?

Any Motec guys want to comment on what the M150 is looking for over can as a wheel speed ?