Vida CEM swapping

McGherkin · Post by **McGherkin** » 26 Dec 2022, 13:54

Those CAN boards look identical to what I'm looking at, so I think we're golden. Basically what I'm planning to do as well!

oscilloscope · Post by **oscilloscope** » 26 Dec 2022, 13:59

McGherkin wrote: ↑26 Dec 2022, 13:54 Those CAN boards look identical to what I'm looking at, so I think we're golden. Basically what I'm planning to do as well!

it certainly works , i would suggest you only purchase a OBD connector from amazon or where ever, the prewired cable are not twisted pair. which i found out after soldering it onto the board. if course it may not matter but its better to have it twisted pair to reduce potential noise. this works a treat with the module on bench too

McGherkin · Post by **McGherkin** » 26 Dec 2022, 14:02

Good info, thanks. As it happens I already was looking at just a bare connector so I'll just grab some ethernet cable for the rest!

I take it you're drawing power from the OBD port too? I've got a few 5v UBECs kicking around from my remote control stuff so I reckon one of those with a nice fat capacitor to iron out the spikes should be good.

5ft24 · Post by **5ft24** » 26 Dec 2022, 14:10

If you dig a bit, there was also a link to PCB files. You can send those to SEEEDSTUDIO and for under 10 bucks have 10 boards made, then just pop the components on yourself. I did that with a 12v to 5v buck converter and a teensy 4.1 and it took under 20 minutes to crack the PIN for my 05 XC90

oscilloscope · Post by **oscilloscope** » 26 Dec 2022, 14:20

McGherkin wrote: ↑26 Dec 2022, 14:02 Good info, thanks. As it happens I already was looking at just a bare connector so I'll just grab some ethernet cable for the rest!

I take it you're drawing power from the OBD port too? I've got a few 5v UBECs kicking around from my remote control stuff so I reckon one of those with a nice fat capacitor to iron out the spikes should be good.

no there is no need to draw from the OBD port as the CAN transducers are powered on the teensy & also powered on the host. . it is worth noting that you should also earth the teensy to the earth on the OBD connector. i was informed to do so on here which i did do.

McGherkin · Post by **McGherkin** » 26 Dec 2022, 14:32

oscilloscope wrote: ↑26 Dec 2022, 14:20 no there is no need to draw from the OBD port as the CAN transducers are powered on the teensy & also powered on the host. . it is worth noting that you should also earth the teensy to the earth on the OBD connector. i was informed to do so on here which i did do.

But what are you powering the Teensy with? On the Schematic on the Github it recommends using a DC-DC converter as the USB power to the Teensy may be insufficient. So I thought about taking an extra 12v from the OBD and using that to power the entire contraption so I can just plug it in, plug the USB into my computer and off I go.

oscilloscope · Post by **oscilloscope** » 26 Dec 2022, 14:34

RickHaleParker wrote: ↑23 Dec 2022, 17:14
dikidera wrote: ↑23 Dec 2022, 16:40 But I also cannot find the device responsible.
You got a Signal Tracer?
You might be able to inject a low powered RF signal at WE and use a tuned receiver to trace the signal to the device responsible

are you referring to a logic pulser or somthing along them lines , for the likes of TTL ?

oscilloscope · Post by **oscilloscope** » 26 Dec 2022, 14:40

McGherkin wrote: ↑26 Dec 2022, 14:32
oscilloscope wrote: ↑26 Dec 2022, 14:20 no there is no need to draw from the OBD port as the CAN transducers are powered on the teensy & also powered on the host. . it is worth noting that you should also earth the teensy to the earth on the OBD connector. i was informed to do so on here which i did do.
But what are you powering the Teensy with? On the Schematic on the Github it recommends using a DC-DC converter as the USB power to the Teensy may be insufficient. So I thought about taking an extra 12v from the OBD and using that to power the entire contraption so I can just plug it in, plug the USB into my computer and off I go.

only via the USB cable. if you are doing the decode on the bench you will need to power the module of course via a power supply as it would normally be in the car.

this is what i use to find the wiring connections out for on bench reads , http://ioterminal.com/docs/docs/iot_volvoecus.pdf

if you also flick back to some previous posts there is also a low side CAN bus. which also aids the process. i didn't do this at first , as it kept on coming up with an error. and wasn't sure why and then it all made sense. x4 wires x2 transceivers , means in total x4 wires connected via obd means 2 separate CAN connections

McGherkin · Post by **McGherkin** » 26 Dec 2022, 14:52

Okay. I think I will still give the Teensy an auxiliary 5v power just to make sure it's sufficiently powered up though.

Yeah the schematic says to connect one of the CAN boards to CAN HS+ and HS- and the other to LS+ and LS-, OBD Pins 6,14,3, and 11 respectively. Plus the CAN Gnd on Pin 5 to the Teensy Gnd, and I can add a 6th wire from the plug to Pin 16 through the 5v converter to power the Teensy.

oscilloscope · Post by **oscilloscope** » 26 Dec 2022, 14:56

McGherkin wrote: ↑26 Dec 2022, 14:52 Okay. I think I will still give the Teensy an auxiliary 5v power just to make sure it's sufficiently powered up though.

Yeah the schematic says to connect one of the CAN boards to CAN HS+ and HS- and the other to LS+ and LS-, OBD Pins 6,14,3, and 11 respectively. Plus the CAN Gnd on Pin 5 to the Teensy Gnd, and I can add a 6th wire from the plug to Pin 16 through the 5v converter to power the Teensy.

no worries , what ever works for you, i didn't and it works no issue using the teensy USB port. admittedly i thought i needed to do so also and i didn't need to in the end. not to mention it was far less wiring to have to do.

edit

i'll have to have alook again but i think the teensy can only be powered either by external power supply or the USB not both.

Vida CEM swapping

Re: Vida CEM swapping