Any questions you have before you begin buying, building and installing.
By Wombat
Hi everyone,

I have been a long time follower of the Speeduino project since I watched Josh get a lawnmower engine running on it back in 2012 ish???

I finally brought a 0.4.3b board off ebay from a bloke in Rockhampton area, but it "might" be bad, as I have the following issues;

1, I cant connect to Tunerstudio when the Speeduino board is fitted to my Arduino board (otherwise it connects fine)
2, On startup, the board draws up to 3A@ 12V briefly, then drops down to 200mA which it draws constantly with no Arduino
board on it or nothing connected to it

I have lifted the first component from each circuit that uses 5v and removed all DIP-8 chips but it still has the same issue.
I am not new to electronics and have a lifetime of experience with them, so im convinced the board may be an issue.
Has anyone else had a similar problem?
I am using the specified components with the exception of the STP62N mosfets (they are on backorder and ending production soon) so am using IRF1405 which are the same pinout and have no connection to the 5V circuit anyhow...

For an introduction:

I used to Megasquirt alot of cars and still have my own from when I was 18- a 1988 Honda Prelude which I MT swapped and turbocharged back in 2003.
It was awesome to be able to build a stand alone ecu which could control fuel and spark back then, I was able to ditch my distributor and use a Mitsubishi evo ignition system, have launch/ anti lag, boost control and a whole lot of other features we take for granted today.
About 5 years ago I changed the engine to a modern B-series engine and have been running it on the standard Honda ECU prior to rebuilding it for big boost (have relocated from NZ to Australia recently and bringing the car with me).

Megasquirt, whilst still going strong in its more modern forms, has become more of a commercial ECU, even though the MS2 kit is still available, its nowhere near as open source as Speeduino, still has B&G proprietary restrictions and does not share the same future potential.
MS1-extra was great at the time but the MC68HC908 MCU is no longer produced and I have decided to move on to this platform and share some personal development I did in private with the Megasquirt platform.

I would like to start with implementing the use of as many "jellybean" components as possible to this project, as semiconductors, especially the chips and mosfets are often hard to find and are regularly being pulled from production by manufactures and make the project unreasonably expensive.

Some components we used in megasquirt builds are

IRL Z44 generic outputs such as idle and boost control
IRF Z34N as injector drivers
2n2222 etc for general relay and low current ignition outputs (although some Speeduino users are using the ULN2003 which is great)

These components are very popular and will continue to be produced almost forever, and can be had for a couple of bucks.
We had no issues with these components at all and although they are older designs, they will work fine for what many of us need...

I would also like to design my own boards and kits in the future once I have tried and tested this prototype I am building on several different engines...

Anyway, thanks in advance for the welcome, I look forward to some engaging discussions with the good people on this forum.


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