Testing JP4 on MS2 v3.0

[brettk]

Hello all,

I have assembled an MS2 v3.0 board and plan on using JP4 on the daughter card as a fuel composition sensor input. Unfortunately the first sensor I tested with was bad. It produced <45Hz signal indicating a sensor fault. The data was received by MegaSquirt and resulted in a -6% ethanol percentage being displayed in TunerStudio. After significant bench testing of the sensor I also found that it occasionally produced a high voltage spike on its output terminal, up to around 12v.

I have obtained a new sensor that is functioning properly. Unfortunately my MS2 no longer seems to be seeing the flex fuel sensor signal on JP4. I have read the following in another thread located here http://www.msextra.com/forums/viewtopic ... 53#p247884:

Well, Megamanual or not, that's a really dangerous circuit and I urge you to change it as soon as possible.

Try the following.


James

PS. The images you linked to earlier didn't work due to the Referr and other access bans that some of the other Megasquirt sites implement.

I am concerned that I may already have fried my MS2. I wired my flex fuel sensor as directed in the MegaManual and did not find instructions for circuit protection until after my problem started.

What can I do to further troubleshoot my JP4 input? I would appreciate any insight that folks here may have.

Thanks,
Brett

[jsdevel]

Did you ever figure out your issue? I've recently installed the JP4 jumper and am wondering if I've fried my MS2 card.