Core voltage low

jykä · Post by **jykä** » Tue Apr 04, 2006 12:43 am

Hi every one. This is my first topic here and excuse me for my basic english

I tried search but couldn find the answer i was looking for.
So ...

My problem is when i try to upload (put in

) altered settings with megatune (engine running) i get popup message saying "Core voltage low .... (and some thing that i can't remenber)" and the setting wount "update" to the controller.

Is this a typical error or is my core voltage really low. And if it is what should i do to get rid of that error.
With pressing "send" button continuously i can get it uploaded but it takes about 10-20 presses before it's done.

My settings are MS-I V2.2 with Extra code/distributor ignition and MT v 2.25b514 (havent tried with 2.25 yet)

Thank you for your time!

T:Jykä

jykä · Post by **jykä** » Tue Apr 04, 2006 10:32 pm

Thank you lance for your reply. I try to tell more about my problem.

As i said, it also does it when car is runing. My alternator makes 13,7V at idle and i suppose that should be enough.

My engine is now in rebuild phase, so i cant test anything but i have been using MS for whole last summer. And if i remember correctly problem was more likely to happed engine running than stopped (voltage engine stopped about 12,4V). Is it possible that RFI interference from ignition could cause this.

Does U1 (prosessor) use row battery voltage or is there regulator to 5V or 12V? I couldn find VCC pins for U1 from schemas.

EDIT: Altough i havent measure voltages from PCB i suppose 0.75mm2 (18 gauge) should be enough to transfer needed power without voltage drop as i also use my-self-build relayboard for idle and gaspump.

Post by **jsmcortina** » Wed Apr 05, 2006 4:47 am

This message more often indicates a serial communications problem. If you are using USB, check the Megatune sub-forum for some USB tips.

James