OBDLink is now powered while car is sleeping

[rrolsbe]

The OBDLink MX in the past was not powered when the car was sleeping (no additional phantom drain). Notice yesterday the two outer LEDs on the MX where illuminated while the car was sleeping. According to the spec the power draw is 2 ma in sleep mode and 69 ma otherwise. Since the power LED was not blinking every few seconds, it appears the MX was not in sleep state. If it was drawing near 69 ma, that is a fair amount of additional phantom drain. Something must have changed in the cars firmware, has anyone else noticed this? I verified there was no data stream present. Maybe the MX is not powered the entire time the cars contactors are open (sleeping)? In the future, I will only plug the MX in while on a trip or monitoring for some other reason. PS, I know the car was sleeping because when I opened the door the contactors opened a few seconds later. Last time I measured the 12V current draw (a few years ago) while in sleep state, it was around 400ma.

 

[ATPMSD]

The OBD port itself is a non-switched 12v source, it is powered all of the time. You can check this with a meter. Perhaps there is an issue with the OBDLink?

 

[rrolsbe]

The OBD port itself is a non-switched 12v source, it is powered all of the time. You can check this with a meter. Perhaps there is an issue with the OBDLink?

That may be true now but in the past 12V was never present when the car was sleeping (AFAIK). BTW, I use the OBDLink MX to access bus data using Scan My Tesla. I am going to plug the MX back in and view the LEDs through the rear window several times during the sleep time. It could be it is not always powered during sleep maybe Tesla started doing something that enables power for a short period during sleep? To be clear what I am discussing in this thread is power during sleep, the MX is always power when the car is awake ie.. the contactors are closed.

Thanks for your reply, regards.

 

[ATPMSD]

That may be true now but in the past 12V was never present when the car was sleeping (AFAIK). BTW, I use the OBDLink MX to access bus data using Scan My Tesla. I am going to plug the MX back in and view the LEDs through the rear window several times during the sleep time. It could be it is not always powered during sleep maybe Tesla started doing something that enables power for a short period during sleep? To be clear what I am discussing in this thread is power during sleep, the MX is always power when the car is awake ie.. the contactors are closed.

Thanks for your reply, regards.

For what is it worth, the standard for OBD-2 (1996 forward) is:

“The OBD-2 connector must have pins 4, 5 for ground connections and pin 16 for 12 volt power supply from the vehicle battery. “

Of course we know Tesla has a habit of doing their own thing.

 

[rrolsbe]

For what is it worth, the standard for OBD-2 (1996 forward) is:

“The OBD-2 connector must have pins 4, 5 for ground connections and pin 16 for 12 volt power supply from the vehicle battery. “

Of course we know Tesla has a habit of doing their own thing.

Yeah, I know what you mean. The Model 3 does not have an OBDII port as delivered. I and many other owners have installed an inline OBDII breakout cable that allows connection of OBDII devices. Will report back to this thread when/if I learn something new. Maybe other SMT owners will chime in? I believe the traction battery cells get low level balanced periodically, certainly not daily, while the car is sleeping which could require data/power to the bus?

 

[GtiMart]

I think you can send commands to your adapter to control its behavior, when it sleeps etc. You might want to have a look at that

 

[ambudriver03]

Yeah, I know what you mean. The Model 3 does not have an OBDII port as delivered. I and many other owners have installed an inline OBDII breakout cable that allows connection of OBDII devices. Will report back to this thread when/if I learn something new. Maybe other SMT owners will chime in? I believe the traction battery cells get low level balanced periodically, certainly not daily, while the car is sleeping which could require data/power to the bus?

I have SMT and the obd/canbus adapter, and the same obd connector you have,


PS : Holy crap. That thing is $140 now?!
I bought mine in December of 2019 for $60
Craziness.

This is the canbus connector I have HRN-CT20T11 - Geotab GO - Geotab Adapters - GPS Fleet Tracking

 

[rrolsbe]

Update after unplugging the OBDLink MX, the time between top offs of the 12V battery is now 27 to 28 hours. With it plugged in, the time to the next top off was typically 17.5 hours or less. I know for sure the MX was not powered in the past not sure when that changed. I have a buddy with a 2019 Model 3 and his MX is still not powered when his car is sleeping.

 

[ATPMSD]

You probably already know this, but just in case:

“…By default, MX is configured to turn off automatically, after 2 hours of inactivity” In such a case the MX will appear to be unpowered even though there is power to the OBD2 port.

If it does not turn off, see this page: Troubleshooting Guide | OBDLink® | OBD Solutions LLC

 

[rrolsbe]

Sorry, I thought my OBDLink was a model MX it is actually an model LX.

 

[rrolsbe]

Has anyone recently measured the Model 3 current draw from the 12V battery when the car is sleeping. The voltage after my M3 tops off the 12V battery for around 2.5 hours is about 13V and the voltage after 28 hours of sleeping is about 12.5V. Appears the power drain from the 12V battery might be as low as 2W which would be current draw of around 150ma. When I measured the 12V battery current while the car was sleeping about two years back, it was around 400-500ma.

 

[Watts_Up]

Has anyone recently measured the Model 3 current draw from the 12V battery when the car is sleeping. The voltage after my M3 tops off the 12V battery for around 2.5 hours is about 13V and the voltage after 28 hours of sleeping is about 12.5V. Appears the power drain from the 12V battery might be as low as 2W which would be current draw of around 150ma. When I measured the 12V battery current while the car was sleeping about two years back, it was around 400-500ma.

I have one of those Clamp meter with Bluetooth remote access recording.
I didn't think about but I would be curious to monitor the battery current draw.
One issue is that I need to remove the frunk cover to access the main 12 V wire.



I noticed that my ODBC2 was still running when my car went sleeping.
This new, as I checked it in the past and the ODBC was off when the car went to sleep.

Note: I recently noticed some strange behaviour recorded with my 12 V battery monitor.
See the following post:

"Proactive" 12v battery replacement - good idea or overkill?

Unless you are monitoring this constantly and see how often your car is charging your battery, no one measurement means anything The monitor and app do all the work of gathering data, I just scroll through the day graphs when I want. It is an easy way to see the voltage of your 12v battery...

teslamotorsclub.com

 

[Watts_Up]

I could not connect my ODB2 device, I noticed that the blue light of the DDB2 device was flashing when this message was displayed on my phone:

 

[rrolsbe]

I could not connect my ODB2 device, I noticed that the blue light of the DDB2 device was flashing when this message was displayed on my phone:

View attachment 812881

I have the LX version but believe the flashing blue LED might mean your MX is trying to pair to your phone. When the green power LED flashes, I think that means the MX is in sleep mode? My LX has a button to initiate Bluetooth pairing looks like the MX also has this button? Maybe someone who owns the MX version can verify statements above. Interesting that your OBD2 is also now powered during sleep. I have a friend with a 2019 Model 3 his LX LEDS are still NOT lite while the car is sleeping (which means to me no 12VDC present).

 

[Watts_Up]

@rrolsbe Well, I apology but I didn't think about because this is new.

So now when the car is sleeping the ODBC2 device is still powered but it seems that the CAN bus is no longer energized.
As a result, the device can be accessed by Bluetooth but cannot connect to the car, explaining the error message that I received.

I noticed that after a while, the ODBC2 device itself goes to sleep, or at least stays in standby.
So when you try then to connect to it, you can notice some handshake messages, and then,
if the car is not sleeping, the ScanMyTesla App is able displays the CAN bus information.

It seems that Tesla received a request to provide a power plug to be always energized, may be from fleets companies like Hertz,
so those companies can easily install a device to localize and communicate with their own vehicles.

I think it's fine to keep the ODBC2 device plugged all the time, I will try to measure the consumption,
but if I remember, I tested a bluetooth rearview camera using Bluetooth and it was using about 40 mA.

 

[thefrog1394]

@rrolsbe Well, I apology but I didn't think about because this is new.

So now when the car is sleeping the ODBC2 device is still powered but it seems that the CAN bus is no longer energized.
As a result, the device can be accessed by Bluetooth but cannot connect to the car, explaining the error message that I received.

I noticed that after a while, the ODBC2 device itself goes to sleep, or at least stays in standby.
So when you try then to connect to it, you can notice some handshake messages, and then,
if the car is not sleeping, the ScanMyTesla App is able displays the CAN bus information.

It seems that Tesla received a request to provide a power plug to be always energized, may be from fleets companies like Hertz,
so those companies can easily install a device to localize and communicate with their own vehicles.

I think it's fine to keep the ODBC2 device plugged all the time, I will try to measure the consumption,
but if I remember, I tested a bluetooth rearview camera using Bluetooth and it was using about 40 mA.

Did you ever test the consumption of the OBDLink?

I don't drive daily, and street park (no home charging), so minimizing phantom drain is a priority for me. Could unplug the OBDLink and re-plug only when needed if it's substantial, although that's kind of annoying.