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v1.1 PNP wont run unless connected to laptop

Posted: Sat Oct 24, 2020 12:36 am
by shirtz
hi guys, i hope this is an easy one. sorry im a newb and i have searched.

i have the above in a mx5 and it wont get any power unless connected to my laptop - doesn't even have to be connected to tuner studio.

i asked the question on FB and lots of comments re dud voltage regulator and "LM7805". im looking at the ECU and i cant find LM7805 no matter how hard i squint! any help with locating it?

i note there is away to bypass it. is there anything else i should look at first? my soldering skills are very bad so id happily pay someone to do it for me if anyone is keen!

Re: v1.1 PNP wont run unless connected to laptop

Posted: Sat Oct 24, 2020 4:03 am
by theonewithin
Check the github that has schematics.

https://github.com/noisymime/speeduino/ ... e/PNPs/NA6

Re: v1.1 PNP wont run unless connected to laptop

Posted: Sat Oct 24, 2020 7:02 am
by dazq
Ok, you can't bypass the 5v regulator, it must have a decent 5v supply!
You won't find an lm7805 as we don't use those! We use the low droput version the lm2940..

On the na6 I believe the mc33814 provides the 5v rail which is not something a novice should attempt to remove

If your soldering skills are that bad , pay someone to fix it. Email one of the suppliers a few do offer repair services.

See the snap shots of the PSU section of a na6 below and the vo4 that uses a LM reg

Re: v1.1 PNP wont run unless connected to laptop

Posted: Sun Oct 25, 2020 6:33 am
by shirtz
thanks for your help guys. found and fixed the problem as per this video at 18:20

https://www.youtube.com/watch?v=A_OzSaS ... manymiatas