# Issue with the gear calculation strategy on EMU Black V3 w/o gearbox sensor

**URL:** <https://community.ecumaster.com/t/issue-with-the-gear-calculation-strategy-on-emu-black-v3-w-o-gearbox-sensor/5469>\
**Category:** EMU BLACK / CLASSIC\
**Created:** [March 31, 2026, 2:31pm UTC](https://community.ecumaster.com/t/issue-with-the-gear-calculation-strategy-on-emu-black-v3-w-o-gearbox-sensor/5469 "2026-03-31T14:31:45Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Drigues](https://avatars.discourse-cdn.com/v4/letter/d/258eb7/32.png) [@Drigues](https://community.ecumaster.com/u/Drigues)\
**Post date:** [March 31, 2026, 2:31pm UTC](https://community.ecumaster.com/t/issue-with-the-gear-calculation-strategy-on-emu-black-v3-w-o-gearbox-sensor/5469/1 "2026-03-31T14:31:45Z")

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As a Formula Student team, we are using the EMU Black ECU to manage our CBR600F4i engine and gearbox. However, we are now having some issues with the gear shifting strategy since we upgraded to the V3 version of the ECU software. As of V2, we were running a calculation gear strategy (the engine from stock doesn’t come with a gearbox sensor, only a ground connection signaling neutral), and we could actuate a external solenoid controller by engaging our paddle shifter even when the gear ratios were not correct. Since we’ve upgraded, there seems to be a newly implemented feature that blocks any outputs being sent to the controller when the ECU doesn’t know which gear the car is. Basically, when we try to shift, the ECU rejects any change and the logs say “Gear shift rejected - Unknown gear”.

I was wondering if this this feature could be toggled as a way to force the outputs to the solenoid controller, like a simple checkbox. I believe this was implemented as to be a safety feature, but for our purposes it acts as a limitation. We have the option to revert back to V2, however the newly added features are much better to use.

Feel free to comment on our implementation and we are looking forward to hear from yall.  
Best regards

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**Author:** ![Greg](https://avatars.discourse-cdn.com/v4/letter/g/71c47a/32.png) [@Greg](https://community.ecumaster.com/u/Greg)\
**Post date:** [April 2, 2026, 1:49pm UTC](https://community.ecumaster.com/t/issue-with-the-gear-calculation-strategy-on-emu-black-v3-w-o-gearbox-sensor/5469/2 "2026-04-02T13:49:40Z")

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Check clutch pedal state . If is on won’t calculate gear.

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**Author:** ![Drigues](https://avatars.discourse-cdn.com/v4/letter/d/258eb7/32.png) [@Drigues](https://community.ecumaster.com/u/Drigues)\
**Post date:** [April 7, 2026, 11:21am UTC](https://community.ecumaster.com/t/issue-with-the-gear-calculation-strategy-on-emu-black-v3-w-o-gearbox-sensor/5469/3 "2026-04-07T11:21:48Z")

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In our case, we haven’t connected any clutch pedal sensor/switch or any think like that. When you say clutch pedal state, are you refering to it being connected or just being invalid? Can you clarify on that please? Thanks for the reply

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**Author:** ![Greg](https://avatars.discourse-cdn.com/v4/letter/g/71c47a/32.png) [@Greg](https://community.ecumaster.com/u/Greg)\
**Post date:** [April 7, 2026, 11:35am UTC](https://community.ecumaster.com/t/issue-with-the-gear-calculation-strategy-on-emu-black-v3-w-o-gearbox-sensor/5469/4 "2026-04-07T11:35:29Z")

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Check what you have on log for clutch status .

maybe is unassigned or something or wrongly assigned