Multiple Connectivity Issues with External Accessories

[Dubbedown]

Background
I am running an iPhone SE2 as my dedicated telemetry device, running Grand Prix v24.9. The only external devices I now use are OBDLink MX Wifi + Bad Elf GPS.

Problem 1 - OBD Device
Today however, the OBDLink MX seemed to stop working. It would not appear in the Sensory List under Available even though I know the device was connected and works. Within Sensory List, if I clicked on All, I then saw a generic OBD device appear... and after few seconds, it changed from generic to OBD MX Wifi, so I thought everything was fine. But upon coming home, I see that none of the engine data was recorded in any of my lap data.

For context, my SE2 wifi connections only 'knows' the OBD Link MX network and I have the setting so that it does not try to connect to any other network.

Problem 2 - GPS Fix
Secondly, must a cellular connection be maintained in order to utilize external GPS devices? My first session did not get a proper GPS fix so lap timer never started. I thought this was odd so I tested using GPS Buddy. And sure enough, I could not get a GPS fix when cellular was disabled. Only when it's on was it then working. I recall being able to use Lap Time with Airplane Mode On - has that changed in the last year or so?

I love the app but I've spent too much money on numerous combo of devices because right when I think I found the right set, something "changes" making those devices unreliable.

1. Kiwi 3 (BT LE) doesn't play nicely with RaceBox Mini (BT LE) -> Buy new OBD Link MX Wifi
2. Racebox Mini connection constantly interrupted by other devices nearby -> Buy older style Bad Elf
3. OBDLink MX Wifi doesn't work with GoPro 4 Wifi -> Just record / sync manually
4. OBDLink MX Wifi now isn't recognized by app at all...


Harry - I could REALLY use your help. I've been a loyal user for 10+ years but in all honesty, the app just becomes harder to use with each release. Back then my GoPoint BT1 + Emprum Ultimate + GoPro 3 worked seamlessly. But now my experience is the complete opposite.

[Harry]

To start with, LapTimer hasn't been changed for some months, so we need to assume this is some issue with the overall configuration.

The OBD MX Wifi has been a difficult device from the beginning. The issue is about keeping the phone connected to its WiFi. This may depend on the OS version. iOS and Android both check if a WiFi connection allows connection to the Internet. In case it doesn't (like any WiFi sensor), it may drop the connection. I'd suggest a cold run at home to not fiddle with it on track. Connect it and monitor how iOS is handling the WiFi connection. It will probably ask whether you want to keep the connection or switch to mobile. Keep the connection. Start LapTimer and make sure the OBD Link is appearing the in the Sensor List after some time. The sensor integration is a generic WiFi sensor implementation, it will change its name once the sensor type is recognized. So what you saw is as expected. Change to Timer view and keep it like this for 30 minutes. Return and goto Sensor List and tap the MX entry. In the sensor details, you can see the number of connections made. It should be 1 or 2 to verify you setup is working.

In case you have the Kiwi 3 around, I sttrongly suggest to use this sensor. While the MX is super fast and great with staying connected, it can be cumbersome.

A cellular connection is not required for the Bad Elf. When switching to Airplane mode, you need to reenable BT (and WiFi) however - both are turned off in Airplane mode.

Racebox Mini will receive a new integration for the upcoming LapTimer Spring release. I have reworked it and dropped the integration the Racebox team provided initially. So you may want to try it again. In general, it requires a high bandwidth transferring data over BT LE at 25 Hz.

- Harald

[Dubbedown]

Harold - thank you for your quick reply. And apologies if I came off overly presumptuous. It's just some frustration on my part as I've made concessions over the years by upgrading/downgrading different devices but I continue to encounter issues on track. Couple things I'd like to address:

1. Yes, I still have the Kiwi 3. However, another reason I switched from Kiwi to MX Wifi is because despite the Kiwi 3 being recognized, it would not record any data. This was the case for both an older and newer vehicle so I don't think it's a vehicle DME issue. And in all instances, I made sure to disable the vehicle's Bluetooth audio. I even went as far as changing Adaptive Timing -> Enabled and ECUs Addressed -> ECM but it did not help. This used to work few years ago on my cars (which has not changed since). But it is no longer the case today.

2. Regarding Airplane mode, I made sure to check that WiFi and Bluetooth were both re-enabled after turning on Airplane mode. Also, for what it's worth, I am pretty sure recent iterations of iOS do not disable those connections; it just disables cellular (or perhaps it remembers your last preference). Nonetheless, I'm not sure why it matters IF the Bad Elf GPS device is connected via Lightning cable and thus does not rely on Bluetooth?

3. I am willing to give Racebox Mini a shot once again but is there any compelling reason I should use that over Bad Elf? I figured a hardwired device simplifies things. I recall having two or more Bluetooth LE devices can interfere with each other in terms of bandwidth (as noted above in my first bullet regarding Kiwi 3 and Racebox).

[Harry]

Yes, wired connection are more stable and I often prefer them too. For Racebox vs. BadElf I'm not so much about update rates - nobody really needs 25 Hz. It is about progress in hardware. While 10 year old OBD adapters are basically the same as today's devices, it is completely different for the GNSS area. You will not only get higher rates, but much higher precision and by far less over-smoothed data today.

Besides the well known issues with the MX Wifi, most issues with OBD arise from old OBD implementations like pre-CAN bus protocols. Especially the early BMW M3 implementation were utter crap and always required fine tuning to work at all. LapTimer uses the automatic bus protocol selection part of the ELM327 standard provided by OBD adapters. For the named OBD implementation they can fail. LapTimer could add protocol-probing (try until it works) to work around this. I never liked approaches like this because they reimplement things / double logic and make everything more complicated. I know that apps like that of OBDSolutions / OBDLink do this instead of relying on the ELM327 mechanism. I do not plan to go into this again, the number of cars requiring this is getting smaller and smaller.