Vida CEM swapping

dikidera · Post by **dikidera** » 16 Jul 2023, 14:09

I have to say, it's a nice scripting language at first glance, thought was put into it, I am still learning it to see how it works, specifically the order of execution, timing etc.

oscilloscope · Post by **oscilloscope** » 16 Jul 2023, 14:33

rkam wrote: ↑16 Jul 2023, 13:45 These are .xml scripts stored in Vida database files
They are part of how Vida links information, text, language, vehicle communication ... together for the user and diagnose tools.

I see I assumed it was as live reading of a task.

Post by **RickHaleParker** » 17 Jul 2023, 00:36

alevol wrote: ↑06 Jul 2023, 12:44 Whan if lower keep alive sending intervals?

On the CEM-B?

On the CEM-B, Stay alive is just to keep the CAN bus connected to the ODB connector. The reason the CEM-B disconnects the CAN is because the CEM-B is a End Node. If the OBD connector was always connected, the CAN signals would reflect off the OBD connector.

If you tap the CAN buses on the other pins you do not need Stay Alive.

matija0610 · Post by **matija0610** » 17 Jul 2023, 04:49

jeffbolem wrote: ↑13 Jul 2023, 00:41 Hey y'all, so I just read the flash off of my spare cem
IMG_6140.jpg
I got data off of the flash memory in hexadecimal, now I don't really know where to go from here. Do I need the entirety of the bin in order to crack the pin, or do I just need the security block, which in Luke's code as "read security block 4000-7FFF" ? I was doing some research on the thread and it seems like I may have to upload the entirety of the bin to D5T5 in order to use the pin with VDash. I am eventually going to change my car's CEM from a bin for an automatic to a manual.

Im really new to this so I appreciate how helpful everyone has been so far!

(had to jury-rig the ground wire, I didn't have enough magnetic arms for it lmao)

send me a .bin
and tell me what needs to be changed in the configuration.

Hectus · Post by **Hectus** » 17 Jul 2023, 14:21

tarbik do you still have some boards and such? if so please shoot me a pm

jeffbolem · Post by **jeffbolem** » 20 Jul 2023, 14:44

matija0610 wrote: ↑17 Jul 2023, 04:49 send me a .bin
and tell me what needs to be changed in the configuration.

I only need to change the gearbox from an AW55 to an m66, which I was planning on doing with Luke's CEM editor for the 2004 brick style cem over OBD2. I am now going down the path of using a ubsjatg to read the bin off of the cem. Which I should be able to put into Luke's tool and modify my CEM as much as I want while it's still in the car.

It would also be nice to enable the foglight to stay on when the brights are engaged, that's something that has always bothered me about these cars.

If there is a way to just change the contents of the CEM bin directly after reading it and then flashing it back on to the CEM while it's still on the bench, that would be nice. Save me an extra step.

alevol · Post by **alevol** » 21 Jul 2023, 00:41

I am afraid it will not be that easy, that you change CEM and get no warnings. The ECM software will keep waiting the transmission to respond.

matija0610 · Post by **matija0610** » 21 Jul 2023, 00:58

jeffbolem wrote: ↑20 Jul 2023, 14:44
matija0610 wrote: ↑17 Jul 2023, 04:49 send me a .bin
and tell me what needs to be changed in the configuration.
I only need to change the gearbox from an AW55 to an m66, which I was planning on doing with Luke's CEM editor for the 2004 brick style cem over OBD2. I am now going down the path of using a ubsjatg to read the bin off of the cem. Which I should be able to put into Luke's tool and modify my CEM as much as I want while it's still in the car.

It would also be nice to enable the foglight to stay on when the brights are engaged, that's something that has always bothered me about these cars.

If there is a way to just change the contents of the CEM bin directly after reading it and then flashing it back on to the CEM while it's still on the bench, that would be nice. Save me an extra step.

it's possible. if you catch me at the computer, send .bin and I'll give you back mod .bin in 10 minutes.

dikidera · Post by **dikidera** » 21 Jul 2023, 05:17

I'm confused. My Denso ECM sees an "effective throttle angle" of a max of 30-35 percent. This is confusing because it is neither 0-100 neither in ° angles

The factor according to DHA is x*1310/65535-15. At 30-35% the throttle plate should be fully open, but again, the max value is 30-35 according to the limiter inside. So how come 30% effective throttle = ~100% actual, because when I look at the throttle plate its fully open, but Effective throttle angle = 30%?

rkam · Post by **rkam** » 21 Jul 2023, 13:05

@jeffbolem

You can read the type of CEM with 40 B9 F0
This is needed to find the correct meaning of the different configuration bytes.

40 B9 FB Vehicle information
40 B9 FC Vehicle type (configuration)

cembrick.csv: (11.72 KiB) Downloaded 114 times

Second byte in response is possibly length + 16*high byte of checksum. Not tested or confirmed.
Third byte in response is 8-bit checksum
Fourth and on is configuration bytes
(Counting from 0 for the byte behind address 40)

Example data length 0x7C, Checksum 0x0152
Byte 2: 0x8C
Byte 3: 0x52

You should be able to find the result of FB and FC blocks in your binary.

0x8000 Vehicle information
0x8100 Vehicle type (configuration)
0x8200 list of checksums for other controllers in the car.

Vida CEM swapping

Re: Vida CEM swapping