OBDLink MX BT too slow

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stefano-c
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OBDLink MX BT too slow

Post by stefano-c »

Good morning,
I've finally bought an OBDLink MX BT to get a faster read from OBD instead a cheap reader but I'm getting the same results.
I'm getting from 0,8 to 1,3 Hz :shock:
My smartphone is an LG G5 SE and the car is a 2009 VW Polo 9N3.

Is it possibly a limit of the ECU of my car? I know it's not an high end car but it's quite modern.

Thanks
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Harry
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Re: OBDLink MX BT too slow

Post by Harry »

The main question is if it has a CAN bus or not. With a pre-CAN bus, you will get up to 2 Hz (i.e. 9 PIDs/s), with CAN anything up to 20 Hz (for the MX).

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stefano-c
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Re: OBDLink MX BT too slow

Post by stefano-c »

Thank you Harry! Is there a way to see if it's a CAN? Is there an indication inside HLT?
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Harry
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Re: OBDLink MX BT too slow

Post by Harry »

No, not currently. You can use OBDLink's own app - it tests the protocols available.

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stefano-c
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Re: OBDLink MX BT too slow

Post by stefano-c »

This is what I've got from their app.
Can be that slow? Is there anything I can do?
Thanks
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Harry
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Re: OBDLink MX BT too slow

Post by Harry »

Yes, it is an ISO 14230-4 KWP - which is pre-CAN and pretty slow. LapTimer is optimized to pull data as fast as possible (it has 9 PIDs / s compared to 4.3 the OBDLink app pulls) and I do not have any levers to make it faster using an ELM accessory.

The only option you have is not reading wheel speed (LapTimer will replace it by GPS speed). This however will not make a big difference and you lose the more responsive OBD speed... Indo Not recommend this.

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stefano-c
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Re: OBDLink MX BT too slow

Post by stefano-c »

Thank you Harry.
I have a 10Hz GPS so I'll prefer to get speed from there. By default HLT takes speed from OBD or GPS?

Let's say I'm interested in just one data from OBD (revs for example) is it possible to set HLT to get just that data at 9 PID/s? This way it would be enough smooth.
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Harry
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Re: OBDLink MX BT too slow

Post by Harry »

You can exclude requests to the speed PID using LapTimer's Expert Settings. All other exclusions will either not add relevant improvements in update rates (e.g. temperatures), or generate issues because LapTimer requires a PID muted. Please search the forum um PID exclusions, we had plenty of discussions on this.

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