Megasquirt Support Forum (MSEXTRA)

With this module how does it work with a CHT rating from 0-200c ? Or is the 1250c a typo? Can 2 channels be used with egt and 2 with cht thermocouple? Hi Harley, As far as we know, many CHT sensors use thermistors, not thermocouples, so you wouldn't need one of these modules for a standard CHT sens...

slow_hemi6 wrote:Fuel pump drive doesn't have an LED indicator on the schematic.

It sounds like he's talking about the corresponding LED on a stim, though he could be referring to D4.

Q2 is the most likely culprit. Do you measure 5V at R16 when the fuel pump ought to be on?

jasaircraft wrote:In my case the mitsubishi pajero manual says its a 0-5v square wave signal, will it still be ok to use the n20 pin29?

Yes, but you may want to remove JP8 on the MS3X card.

Please post a copy of your MSQ file and a data log of the engine running while the problem is occurring.

The stepper driver chip should shut down if it overheats, but a dead short may cause damage. Does the large chip on the MS2 card get hot to the touch?

slow_hemi6 wrote:When I look at the pin usage chart it says JS0 is a possible Tach pin. It does not say this for JS1.

JS1 can be used; it will generate the inverse of the signal on JS0, but that doesn't matter much for a tachometer output.

Assuming you are referring to the DIY auto tune diagram, if the 3A fuse is pulled, or blows for some other reason and the key is on, the inj and coils will be powered w/o the ECU. Sure, you would not leave they key it on all day like that, but full current would be applied to your injectors at that...

Though we prefer to have the MegaSquirt ECU control power to the injectors and coil through the fuel pump relay output, that's also an appropriate way to wire it. Everything is controlled by the ignition switch, so the injectors and ignition coil can't be powered independent of the ECU.

Thanks for the reply. Looking at the 'official' external wiring guide, that seems like it would work out better. I'll have to convert over to that from what I have now. I'm a bit disappointed... I tend to think very highly of Symtechlabs, but if you check out their 420a schematic, I've wired it ver...

Your MegaSquirt ECU has a few circuits built in the proto area (they look like a general purpose output and tachometer output). If you don't want or need these circuits, just remove them and connect JS0-JS3 to the IACxx pins like normal. You will also have to relocate the second ignition driver outp...

thecrew2999 wrote:Lookong at bip373 left leg goes to ms3... middle leg goes to coil ... right leg goes to ground

Are the BIP373's isolated from ground? The tabs are connected to pin 2, so if they're not isolated, the coils will remain permanently energized.

This particular circuit actually has nothing to do with your MegaSquirt ECU, so when you rebuild it, you don't have to keep it in the proto area.

nathaninwa wrote:everyone has a different duty cycle. I like to not exceed 85% dc. others are at 80%, and some will say 90% as long as afrs are in the mid 11's.

We agree, about 80-85% is the maximum.

By default, there should be a pulsewidth gauge on your TunerStudio dash. Does the needle on this gauge move when the engine is cranking? The ECU needs at least power and an RPM signal to fire the injectors. Please post a data log of the engine attempting to start if you need further assistance. http...

In general, you simply have to set the "number of coils" setting to "single coil," but that setting shouldn't even be available if you selected "EDIS" as the spark mode. http://www.msextra.com/doc/ms2extra/MS2-Extra_EDIS.htm#Edissoft Please post your MSQ file and the ex...

Hi Folks - just a quick question about Bluetooth speeds. Am I correct in understanding that when you use Bluetooth on a MS it's really just a wireless interface to a RS232 port? If so, does that mean that, for instance, your Bluetooth module supports Bluetooth V4 then it's largely irrelevant becaus...

unimog wrote:So your saying I have to order 2 looms? One for ms3 main board and one for the expansion card.
I understand a lot about this unit except this.

Yes, there are two plugs and two harnesses.

I know 0 about code and c programming. I simply want to open the MS3 code and read it and be able to learn wha tthe code does and how. I downloaded notepad++ and opened the MS3 s19 file and all I see are lines of numbers rather than text that I could maybe understand . Am I doing it wrong? At this ...

You might have your positive and negative multimeter leads backward.