Fix for UAEFI sometimes not starting without USB connecteed
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Fix for UAEFI sometimes not starting without USB connecteed
5vp does not light up with just 12v below a certain battery voltage, causing a no-start condition
this was traced down to a severe enough drop at the main 5v regulator that would cause the main MCU to power down, aborting enabling 5vp, entering a loop.
fix is rather crude, but it's to force 5vp to initialize forcefully, MCU or not.
10k resistor between pin 7 and 5v rail, like in the picture.
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1994 6speed supra turbo [ single turbo/1000cc ID/twin fuel pumps/bc2 262 cams ]. J&S safeguard for knock , UAEFI / 407 disco with rusefi / AEM EMS v2 / MS3pro PNP / Speeduino (mega2560 / teensy41 / stm32f411)
2020 BMW X3m - bootmod3 stage1
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Re: Fix for UAEFI sometimes not starting without USB connecteed
We still do not know real root cause right?
Similar looking boards one would work another would not, right? https://github.com/rusefi/uaefi/issues/59
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Re: Fix for UAEFI sometimes not starting without USB connecteed
correct, still don't know the actual root cause, just breadcrumbs of symptoms with comparison to good board
1994 6speed supra turbo [ single turbo/1000cc ID/twin fuel pumps/bc2 262 cams ]. J&S safeguard for knock , UAEFI / 407 disco with rusefi / AEM EMS v2 / MS3pro PNP / Speeduino (mega2560 / teensy41 / stm32f411)
2020 BMW X3m - bootmod3 stage1
2020 BMW X3m - bootmod3 stage1
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Re: Fix for UAEFI sometimes not starting without USB connecteed
Not to necro an old thread but this might still be the case. Have a UAEFI hooked up to a bench power supply putting out 12v with nothing connected besided power and ground and it appears the 5v rail isn't firing up. When I plug in the usb to a laptop the 5v rail stays up even when removed. I don't have a variable power supply but it looks like even as low as 12.2 and I don't see it kick on. Can be a bit inconsistent though. I have had a case where I know the battery was low and the 5v line fired up fine, enough to bump start and get the generator spinning but not enough to use the starter.
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Re: Fix for UAEFI sometimes not starting without USB connecteed
Very limited telepathic abilities - please post logs & tunes where appropriate - http://rusefi.com/s/questions
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Re: Fix for UAEFI sometimes not starting without USB connecteed
Anche la mia uaEFI personalizzata aveva il problema discusso in questo post
Per risolvere il problema ho eliminato R141 e aggiunto R142 nel modulo mega-mcu-100
con questa modifica funziona perfettamente.
non sò se è la soluzione corretta, non ne ho trovate altre.
Per risolvere il problema ho eliminato R141 e aggiunto R142 nel modulo mega-mcu-100
con questa modifica funziona perfettamente.
non sò se è la soluzione corretta, non ne ho trovate altre.
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