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OBD port and accessories PSA

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Just got my vehicle back from the SC for some warranty work and had them run a check on my logs since I've had issues with the last two updates failing to download several times.

The ran a bunch of tests and from what they told me as the vehicle is downloading or validating the firmware the draw of 12 volt power from the OBD II port to my dash cam causes it to glitch and download fail (had to them push the last 2 updates OTA). Said they've been seeing it pop up on vehicles that have something hooked up to the OBD port and pulling constant power. They were able to test and replicate the issue (mobile app said I had a new update ready but it was the SC testing to replicate the issue).

Recommended to disconnect from the OBD II port when a firmware update comes out or time it so that the dashcam will auto shut off.

Thought I'd share for anyone having issues with not getting firmware updates. Call in and have them check your logs for failed downloads and if you have dashcam or other accessory drawing power from the OBD II port disconnect it see if that helps.
 
This is a very good PSA. I'm having the same issue with my MS 100D (Nov 2017). Had to take it in in March after 4 out of 5 update failures. The OBD II device was the issue (although the previous 5+ updates worked fine). However, I stopped receiving updates, so I had to bring it back in earlier this month. They pushed the latest update but can longer get updates to install even without the OBD II device in it.
 
This is a very good PSA. I'm having the same issue with my MS 100D (Nov 2017). Had to take it in in March after 4 out of 5 update failures. The OBD II device was the issue (although the previous 5+ updates worked fine). However, I stopped receiving updates, so I had to bring it back in earlier this month. They pushed the latest update but can longer get updates to install even without the OBD II device in it.

My SC rolled my update back and reinstalled. Guess I'll have to wait and see if the 2018.16 will download this time.
 
Do we know if this is only for always-on power provided by the OBD II port, or is it any device drawing always-on 12V power (dashcam wired through the unused cable behind the speaker grill)?

It may vary by build or phase of the moon too. But FWIW... my 2016-Q1 90D gets updates on a regular basis, once a month or so, and it has two cameras powered by that unused cable.

Another possible factor: @battleroyale was your vehicle plugged in when these updates failed?
 
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It may vary by build or phase of the moon too. But FWIW... my 2016-Q1 90D gets updates on a regular basis, once a month or so, and it has two cameras powered by that unused cable.

Another possible factor: @battleroyale was your vehicle plugged in when these updates failed?

My car wasn't plugged in. It was from the always on power OBDII port (my dashcams are on 24/7). The SC said that the car goes through some sort of validation cycle and if the car senses 12 volt power being drawn from the OBDII port it could cause the download failure. They were able to replicate it and said they've been seeing it happen more often. (Pre autopilot P85+)
 
Damn. Just bought an Owl cam and now wonder if I want to deal with this. I guess I will just have to remember to unplug when updating, which at present requires a trip to the car anyway, though in the future I'd like to think we can trigger an update from the app. Thanks for the PSA.
 
Damn. Just bought an Owl cam and now wonder if I want to deal with this. I guess I will just have to remember to unplug when updating, which at present requires a trip to the car anyway, though in the future I'd like to think we can trigger an update from the app. Thanks for the PSA.

Thats what I plan on doing when an update starts to roll out and vehicle is parked and on wifi.
 
Yeah, people have had power attached to the OBD port for years. Not sure why they would care now or ever about what is using that source of power. If they want to stop accessory usage, this is going to be a mess. And especially when we have no way to know when an update is coming. Now if they mean pull the power drain when you tell the update to install, okay, but I can’t think of any reason this was added.
 
Never had any problems downloading firmware while having Blackvue Dr650s-2ch plugged into the OBD port, but ever since 18.2 my Blackvue dashcam does not seem to be able to draw enough current to boot successfully and record videos.
 
Do we know if this is only for always-on power provided by the OBD II port, or is it any device drawing always-on 12V power (dashcam wired through the unused cable behind the speaker grill)?
The unused 12V in the microphone grill is on its own circuit and fuse direct from the 12V battery (it's the Alarm fuse, since it's used for European car alarm option). I've had 4 Teslas, one of them new MCU, using it for dashcam, no problems getting updates or otherwise - the only side effect is slightly higher vampire drain as the dashcams run 24/7, but not enough to trip a Tesla service warning (which happens if the 12V battery needs to be topped off from the HV battery too often).
 
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