Vendor Scan My Tesla, a CANBUS reader for Android

[aerodyne]

A true Festivus miracle has happened!

A few months ago my car was reporting one cell around 85mv lower than the rest. It's now only 6mv and my range has gone up by 8 miles!

I had a cell up to 40 mv out if balance a while back, after a long period of storing the car at less than 70%.

After some driving and a few charges to 75%, I see only about 8 to 20 mv.

Picked up about 4 miles. I guess it is true what WK057 said about the BMS, it is pretty amazing.

 

[hybridbear]

This is an OBDLink firmware problem. The adapter locks up, stops responding to any commands from the app. Then app occationally crashes, which of course does not make the sitation any better. Or, the truth is, I have reported this problem to OBDLink for years, they have spent a lot of time trying to recreate the issue in their lab, but they can't. I honestly don't know where the problem is, but I know if I connect even a Windows laptop to the adapter after this happens, Windows also doesn't get any response from any command, even ATZ (reset). I suspect it also could do with the phone's bluetooth implementation, some phone brands are bad, some are perfect.

Some things to try:
- The OBDLink app has firmware updates, try that for starters
- Try to run less data through the app, don't always use the All tab but use the other premade ones, or create your own

With my equpment this only happens after recording CAN dumps for longer periods (usually 20+ minutes). Unless I do this I rarely see this problem, and I run the app literally 24/7 in the car for years. In my case the OBDlink loses power when the car sleeps, this makes it always boot fresh every day, you could check if your wiring harness allows this, if it doesn't you can move one pin on the car side to pull a 12v source that goes offline when the car is sleeping.

I updated the firmware of the OBDLink MX and it hasn't really made a difference. Now instead of Scan My Tesla crashing after less than 10 minutes it crashes after about 15-17 minutes. I don't get with Scan My Tesla has this issue. I've owned my OBDLink MX since 2014 and I've used it for hours & hours at a time running Torque Pro on road trips with my previous Ford Fusion Energi. I'd also used it for extended periods with my previous Ford Focus Electric running FORScan. Neither of those apps ever had any issues with the communications between the app & the OBDLink MX like Scan My Tesla does...

 

[amund7]

I updated the firmware of the OBDLink MX and it hasn't really made a difference. Now instead of Scan My Tesla crashing after less than 10 minutes it crashes after about 15-17 minutes. I don't get with Scan My Tesla has this issue. I've owned my OBDLink MX since 2014 and I've used it for hours & hours at a time running Torque Pro on road trips with my previous Ford Fusion Energi. I'd also used it for extended periods with my previous Ford Focus Electric running FORScan. Neither of those apps ever had any issues with the communications between the app & the OBDLink MX like Scan My Tesla does...

Me too, my first MX was probably that old. This is very different from Torque: ODB2 != CAN, and 1000 packets per second != torque's rather slow OBD2 traffic. We are using the OBD adapters for something they weren't meant to do extensively, and I think we are also pushing the limits of the phone's bluetooth stack. It seems to me different phone manufacturers (and also different Android versions) behave differently. I could never figure out where the problem occurs, it seems to be a combination of phone type and firmware + Android version, my app code, and the OBDLINK, can't place the blame until we find it. But it seems the combination of these things sometimes (or quite often in your case) pushes the OBDLINK into a corner it wasn't designed to be, and it locks up. You can confirm this by trying to connect other apps to it, or just a bluetooth terminal after it's hung, no response from any commands. It does not happen to other brand OBD adapters. OBDLINK has spent a lot of time trying to reproduce the bug in their lab, also sent out capture devices to one of my users, but they can't record or reproduce it.

 

[hybridbear]

Me too, my first MX was probably that old. This is very different from Torque: ODB2 != CAN, and 1000 packets per second != torque's rather slow OBD2 traffic. We are using the OBD adapters for something they weren't meant to do extensively, and I think we are also pushing the limits of the phone's bluetooth stack. It seems to me different phone manufacturers (and also different Android versions) behave differently. I could never figure out where the problem occurs, it seems to be a combination of phone type and firmware + Android version, my app code, and the OBDLINK, can't place the blame until we find it. But it seems the combination of these things sometimes (or quite often in your case) pushes the OBDLINK into a corner it wasn't designed to be, and it locks up. You can confirm this by trying to connect other apps to it, or just a bluetooth terminal after it's hung, no response from any commands. It does not happen to other brand OBD adapters. OBDLINK has spent a lot of time trying to reproduce the bug in their lab, also sent out capture devices to one of my users, but they can't record or reproduce it.

Send me the capture device & maybe I'll be able to get something useful for OBDLink...

 

[amund7]

Send me the capture device & maybe I'll be able to get something useful for OBDLink...

I never got one, it was sent to a Scan My Tesla user who reported the issue to OBDLINK. If you're interested PM me and I can forward the email to the right person in OBDLINK.

 

[hybridbear]

I never got one, it was sent to a Scan My Tesla user who reported the issue to OBDLINK. If you're interested PM me and I can forward the email to the right person in OBDLINK.

Message sent. I'm happy to try to help.

 

[JWardell]

These all sounds like common traits I've experienced with multiple OBDlink models and firmware versions. The problem seems to be even worse if your OBDlink is always powered. Some harnesses are built incorrectly and supply 12v power from the wrong wire. If you fix the harness so the power turns off when the car sleeps (move to the accessory wire), OBDlink will behave a bit better with power off more often. But it doesn't completely fix the problem.
Ultimately none of these devices were intended to handle all this data

 

[hybridbear]

These all sounds like common traits I've experienced with multiple OBDlink models and firmware versions. The problem seems to be even worse if your OBDlink is always powered. Some harnesses are built incorrectly and supply 12v power from the wrong wire. If you fix the harness so the power turns off when the car sleeps (move to the accessory wire), OBDlink will behave a bit better with power off more often. But it doesn't completely fix the problem.
Ultimately none of these devices were intended to handle all this data

How do you modify the cable to do that? I have the Maxwell cable.

 

[israndy]

Some harnesses are built incorrectly and supply 12v power from the wrong wire. If you fix the harness so the power turns off when the car sleeps (move to the accessory wire)

I noticed that my CANserver is always on, I guess my adapter is wired wrong, but I not notice any issues, no undo battery drain or problems with the data. It's kinda nice to communicate with the car even when it's not talking to the Tesla App.

 

[Decibelle]

Hi amund7,
I just purchased the app for iOS and while I think most numbers are correct, it seems like the Nominal Full Pack, Nominal Remaining, and Expected Remaining numbers are a "touch" high. Please see screen shot. Any thoughts?

 

[amund7]

Hi amund7,
I just purchased the app for iOS and while I think most numbers are correct, it seems like the Nominal Full Pack, Nominal Remaining, and Expected Remaining numbers are a "touch" high. Please see screen shot. Any thoughts?

View attachment 619541

Congrats on the first Cybertruck!

Check settings -> before/after FW 2020.20.5 and match that to your car's firmware. It should default to after this firmware, and I thought all cars should be on those firmwares by now.

 

[Schulmann]

I just received my OBDLink Mx before Christmas !

Before I was using an old ELM 327, it was slow to start and was updating every 3-4 seconds my screen.

I have 3 minor issues with the OBDLink Mx (My cell is a Samsung S9+)
- I believe it send too much data to the ScanMyTesla application.
- Data changes too quickly on my cell phone screen, it is difficult to follow the values.
- Sometimes application freezes, I have to reboot OBDLink and restart app.

Is there a way to add a parameters to the application : Sampling intervalle ? (Put a sleep in the code ?)

 

[amund7]

I just received my OBDLink Mx before Christmas !

Before I was using an old ELM 327, it was slow to start and was updating every 3-4 seconds my screen.

I have 3 minor issues with the OBDLink Mx (My cell is a Samsung S9+)
- I believe it send too much data to the ScanMyTesla application.
- Data changes too quickly on my cell phone screen, it is difficult to follow the values.
- Sometimes application freezes, I have to reboot OBDLink and restart app.

Is there a way to add a parameters to the application : Sampling intervalle ? (Put a sleep in the code ?)

Canbus doesn't work that way, but the car sends different packets at different speeds. The app tries to display what it gets. What the app does is to filter out only the traffic you have in your current tab. You can gauge the stress by looking at the OBDLINK lamp, try the temps tab for instance, you will see only a rare blink.

- Performance data (battery power, motor power, torque values, and also throttle pedal + steering angle): 100 Hz
- HVAC stats and cooling system info: 1 or 10 Hz
- Most temperatures, historical battery stats, odometer: 1 Hz

The default tabs are built with this in mind. You can also delete signals you're not interested in, or bulding your own new tabs. You should never really need to use the All tab for anything else than finding and copying signals over to other tabs. I have measured up to 1100 can packets per second with an OBDLINK, model 3 and All tab. Each packet contains everything from 3 to 10 signals! That is really a lot of processing and UI updates going on.

The OBDLINK can benefit from a firmware upgrade, check/update with the official OBDLINK app.

But yeah, the OBDLINKs do have this problem, I have worked with OBDLink to try to find a solution, but we can't really find the root cause. It could also be bugs in my code, and different phone brands seem to behave differently, so most likely it's a mix of my app + phone bluetooth drivers and/or too much Tesla CAN traffic and non-standard packet lengths that triggers something in the OBDLINK to hang.

Next time this happens, try just unplugging/replugging the OBDLINK, you shouldn't need to restart the app. Try with less/slower data and see how that works out for you. Besides this, the only thing I can suggest is contacting OBDLINK support, maybe if enough people do that they will put more efforts into solving it.

 

[hybridbear]

Canbus doesn't work that way, but the car sends different packets at different speeds. The app tries to display what it gets. What the app does is to filter out only the traffic you have in your current tab. You can gauge the stress by looking at the OBDLINK lamp, try the temps tab for instance, you will see only a rare blink.

- Performance data (battery power, motor power, torque values, and also throttle pedal + steering angle): 100 Hz
- HVAC stats and cooling system info: 1 or 10 Hz
- Most temperatures, historical battery stats, odometer: 1 Hz

The default tabs are built with this in mind. You can also delete signals you're not interested in, or building your own new tabs. You should never really need to use the All tab for anything else than finding and copying signals over to other tabs. I have measured up to 1100 can packets per second with an OBDLINK, model 3 and All tab. Each packet contains everything from 3 to 10 signals! That is really a lot of processing and UI updates going on.

The OBDLINK can benefit from a firmware upgrade, check/update with the official OBDLINK app.

But yeah, the OBDLINKs do have this problem, I have worked with OBDLink to try to find a solution, but we can't really find the root cause. It could also be bugs in my code, and different phone brands seem to behave differently, so most likely it's a mix of my app + phone bluetooth drivers and/or too much Tesla CAN traffic and non-standard packet lengths that triggers something in the OBDLINK to hang.

Next time this happens, try just unplugging/replugging the OBDLINK, you shouldn't need to restart the app. Try with less/slower data and see how that works out for you. Besides this, the only thing I can suggest is contacting OBDLINK support, maybe if enough people do that they will put more efforts into solving it.

Very interesting about the frequency of different types of data. I will check out the OBDLink lamp to see variations with different tabs. To try to reduce stress on the car since my OBDLink MX has been crashing I've tried creating a custom tab with just the data I'm most interested in so that I don't have to switch tabs as much. This has seemed to help. OBDLink Tech Support has also been very helpful. They are going to send me a logging device to try to capture why their adapter fails. I would encourage anyone with issues to contact them through their website scantool.net.

Is there a way to rename tabs? Right now my custom tab just says "new". I'd also like to reorder them if possible, but I haven't seen a way to change the order...

 

[Decibelle]

Congrats on the first Cybertruck!

Check settings -> before/after FW 2020.20.5 and match that to your car's firmware. It should default to after this firmware, and I thought all cars should be on those firmwares by now.

Thanks for the reply! I had changed the setting to reflect my earlier firmware so that was not the problem. I just went downstairs and hooked up the Android and it showed the correct numbers. Then I hooked up the iPhone and the numbers now seem to be fine. I will continue to watch and if it comes back, I will let you know. Please keep the option to use SMT for older firmware cars.

 

[amund7]

Thanks for the reply! I had changed the setting to reflect my earlier firmware so that was not the problem. I just went downstairs and hooked up the Android and it showed the correct numbers. Then I hooked up the iPhone and the numbers now seem to be fine. I will continue to watch and if it comes back, I will let you know. Please keep the option to use SMT for older firmware cars.

Note that the IOS version needs a restart (you have to press Exit from the menu) to reflect these changes.

This is the only set of signals that are switchable - there are lots and lots of signal changes over the years that have been changed in the app from version to version, especially with Model 3/Y while S/X has stayed relatively constant. It would be pretty impossible to keep all versions of all signals at all times, and keep track of when they changed so basically I can't support older firmwares for all signals. For Model 3, just a 2 months old firmware at this point would probably break 20 signals or so...

 

[amund7]

Very interesting about the frequency of different types of data. I will check out the OBDLink lamp to see variations with different tabs. To try to reduce stress on the car since my OBDLink MX has been crashing I've tried creating a custom tab with just the data I'm most interested in so that I don't have to switch tabs as much. This has seemed to help. OBDLink Tech Support has also been very helpful. They are going to send me a logging device to try to capture why their adapter fails. I would encourage anyone with issues to contact them through their website scantool.net.

Is there a way to rename tabs? Right now my custom tab just says "new". I'd also like to reorder them if possible, but I haven't seen a way to change the order...

Just wanted to point out one thing, we're not stressing the car. The obdlink just listens to traffic passing by. By reducing the signals you are only reducing stress on the OBDLINK and your phone, and the scan my tesla app. The car does not know we are there, except the few milliamps of power the OBDLINK might need to power itself from the 12v line.

Renaming of tabs can't be done, bottom up full rewrite / new app coming soon. Well soon in Elon time, it should come soon to beta at least.

 

[MarcG]

Hi @amund7 I've noticed in the last few weeks that the min/max battery voltages are about half as much as they should be.

In the example screen shot, Min pack voltage is 121V (used to be 240-242V), Max pack voltage is 202V (used to always be 403V), yet Battery voltage is 384V

Also, the Drive total and Regen total seem to be way off (should be closer to 13,000 and 3,500 kWh, respectively).

Any idea why that might be going on? New firmware updates perhaps?

 

[JWardell]

Those all changed in .48

 

[amund7]

Hi @amund7 I've noticed in the last few weeks that the min/max battery voltages are about half as much as they should be.

In the example screen shot, Min pack voltage is 121V (used to be 240-242V), Max pack voltage is 202V (used to always be 403V), yet Battery voltage is 384V

Also, the Drive total and Regen total seem to be way off (should be closer to 13,000 and 3,500 kWh, respectively).

Any idea why that might be going on? New firmware updates perhaps?

View attachment 626819

These were fixed in Scan My Tesla 1.9.3 released December 13, 2020. After that we released 1.9.4. Keep up man!

The max and min pack voltages were missed that time, I have found a solution and it's in the pipeline for next release.