Onto vs BMW GOM

Hi all. Not sure if this is i3 specific as it’s the only car I have had so far and sorry if it’s a repeat question (just point me at the previous answer). I did have a search but I couldn’t find an answer.

Does anyone get a different range in the onto GOM vs the the BMW one (app or in car?). They both show the same battery % but the onto one always seems to show higher range than the BMW one for me. To be fair the onto calculation seems a bit more reliable if anything and the BMW one is all over the place on short runs (which is mostly what I am doing) they seem a bit closer if I am doing 30+ miles. Just wondered if anyone else has same (or different) experience and which one you have found to be most accurate over time.

ONTO can only grab the charge level from the car, not the GOM estimate. What you see is a fixed number and then they will calculate your percentage of what they think the real world range of that model is.

Meanwhile the car can make dynamic estimates based on your recent driving style and other variables that will impact your range.

So it’s preferable to go by the vehicle GOM rather than the ONTO calculation. Then in addition do a sense check on what the vehicle says with a bit of mental arithmetic using current SoC % and your average mpkWh. GOMs can lie like a rug :wink:

Not necessarily. It’s dynamic estimates are a little too dynamic for my liking! It’s similar to the LEAF where it would jump all over the place. If you go up a hill it instantly drops your range. Go down and it will very quickly add back to it. Acceleratre quickly or put the heater on and it isn’t very forgiving.

I Prefer cars like the Zoe in this sense. It gradually adjusts based on recent averages so you don’t get a sudden shock in response to a minor change in conditions. It makes it easier for me to work out how much range I really have at any given time.

Since ONTO Mostly just use Pod Point’s real world ‘confidence’ range, the app does actually tend to give you a better idea (If it regularly updates - I’ve had a few occasions recently where this data can be hours or even days out of date)

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Best bet, I think, if you want accuracy and real reassurance on journeys where you think you are going to be getting close to (or know you are going to exceed) your current range is to use the driving mode in ABRP.

I just tend to ignore GOMs completely on longer trips.

If whilst you are driving something happens that starts to affects your consumption (heavy rain, traffic jam, diversion etc) so that your 'current SoC is higher/lower than the ‘planned SoC’ then you just adjust the ‘current SoC’ in the app with the arrow buttons and you’ll then see how that affects the estimated arrival SoC at your destination, waypoint or next charging stop. Complete knowledge in real-time where you stand, and no guessing, no mental-arithmetic etc.

(It’d be nice if we could use the ODB ports, as then the current SoC could be adjusted automatically)

This is about the best demo I can find on YouTube:


Thanks all! I like ABRP as a tool - wish I they would allow plugins in Waze!

Will also keep an eye on it and and I appreciate that while vehicle GOM is Providing a better instantaneous range indication- which I suppose it’s what it is there for would be nice to have an averaged out one too based in the last trip reset (like the ‘miles until empty’ on an ICE car) as I have had several cars where you could have both. Maybe the i3 does that too but I couldn’t find it. I guess it’s better to avoid the confusion - but I’d like to have more things to play with!! It just seems to be all over the shop on the i3 at least!

The i3 GOM does adjust if you input a destination into the car’s sat nav. So if you’ve been bimbling around town all week and then at the weekend decide to do a 200 mile motorway journey, it’s best to make sure you enter the destination into the car sat nav — even if you then mute it and just use Waze or Google on your phone.

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O/T I know but Satnavs should be seen and never heard in my opinion!

First thing I do is mute the spoken directions- had an infuriating experience with an E class last year discovering you could only adjust the volume during a spoken announcement and not just turn it off!

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Thanks. Good point!!

I’m with you. Ever since TomTom, Garmin (and others) and then the likes of Google, Waze (Google) and others came in the scene I have wondered how manufactures ever managed to charge satnav as a several thousand pound option - less often the case now but even so it is still often part of a pack.
It’s one of the reasons I like CarPlay/Google Android auto - hoping more manufacturers allow it on the dash/hud displays as I still have yet to find a manufacturer satnav I liked better than Waze!

Definitely worth taking the time to setup the favourite buttons in the i3 — I had one to toggle the nav voice, a couple for frequent destinations, one to turn on ‘auxiliary climate’ etc