I am finally started on the actual engine management portion of my project car. I posted on the MS3 support forums but thought that I could use all the help I could get. I will have more questions shortly I know it lol! The thread is located: http://www.msextra.com/forums/viewto...?f=131&t=38195 Does anyone have experience enough to helo me and answer a few questions? Thanks Everyone

I am starting to assemble my megasquirt 3 w/MS3X and I have a few general questions while following the instructions here http://www.msextra.com/doc/ms3/build_manual.html . This will be going into an 88 T2 Mazda RX7 w/a 89 motor.

Step 4: why is R57 in the kit if it's never actually needed as the step says?
Step 13: I installed C30 into H1 boot, I hope this was correct. I want to use spark as well so I thought this was correct for me... Does this mean that nothing will end up going into the C30 spot at all?
Step 18: I did not smear any thermal grease on Q9 & Q12 since there is the mica insulator there. Is that the correct way?
Step 19: It says to solder the Y1 crystal to the board just for completness. Should I also solder the leads? It doesn't specify... If I do not I worry about intermitant contact, and I don't know if it will be a problem if there soldered in either...
Step 20: I left on a buisness trip at this point, about to solder the MAP sensor in place... It says to solder SPR1-4 in first if I need them. Are these the 4 spark outputs I need since I will be using the MS3 to control everything? If so, how long should I make the jumper wires and do I need them?
Step 21: Should R37 & R38 also get a smear of thermal grease??
Step 22: I assume I will be using the Q16 since I will need ignition? I will be using the stock FC coils and such if that makes any difference. So that means I may one day need R43 installed for testing purposes? If I install it but never use it, will this hurt anything?


I will start testing once I can get through all of these questions here... I appreciate any and all help or suggestions

 

sure, I am one of the firmware writers and own an rx7 that is running MS3+MS3x

No idea, that's a question for DIYAutoTune.

Yep.

Doesn't really matter one way or the other since the ms3x board will be driving your injectors.

Doesn't matter, just so you know though, those instructions meant to solder in the leads only.

Spark outs are on ms3x board. You don't need to do anything here.

Won't hurt but won't help either since you will be driving injectors from the ms3x board.

You don't need either of them, the ms3x will be used for ignition.

Ken

 

Thanks for all the great 1st hand knowledge! I will def need some more help later but 1st I have to apply all this and figure out what's wrong with my megastim before I can move any further Hopefully I'm driving soon!

 

what problem are you hqving with the stim?

 

I just finished building my jimstim 1.5 and all the leds tested good, but when I do the tach test I get nothing... So I checked all the voltages on the board with a multimeter using the pin headers... here is what I read:

3.3v = 2.9v
12v = 7.03v
5V = 0v

Nothing gets hot even after leaving it on for an hour...

Oh no, what did I forget/break?

I had a feeling that this would happen... some of the solder joints refused to flow properly in this kit... on the actual MS kit all the joints have flowed very beautifully/solidly so I hope there is less to go wrong there...

 

What are you using to supply power to the JimStim?

The 3.3 being 2.9 doesn't seem too terrible, but the +12 being 7.03 and the +5 being 0 seem bad.

Seems like +7.03 going to the MS isn't enough to make the regulator work so you're not getting +5 back out of the MS.

Ken

 

Ohh, it's not hooked up to the megasquirt... I wanna get the stim working properly before I try that...

The power supply is a walwart supplying the jimstim with 9vdc 200mA. That may be a problem lol! My bad... Ok, just cut up another walwart supplying 12vdc 600mA and my voltages are a little higher at:
3.3V = 3.007
12v = 9.82
5v still nada... This is because it's not hooked up to anything right?

Using "http://www.kpsec.freeuk.com/components/ic.htm" as a ref for the pin locations I followed "Troubleshooting tach signal, CPU and 3.3V" at "http://jbperf.com/JimStim/JimStim_v1_4_assembly.html" and found the following:

pin1 and pin3 have voltage, pin 13 and 14 do have voltage that varies with the fine and course pots... so that all checks out good... I also just desoldered a few "shoddy" looking joints and used my good paste(just got it) to solder them again and they look real good now! But it still doesn't work no changes...U think the regulator is bad since the 12v is so low? It doesn't even hardly get warm...

Edit: Just tried this... Using the middle pin as a ground ref on the regulator, one pin reads 3.055v and the other 9.91. This is measuring at the regulator itself. Checking the voltage into the jimstim is 10.63v. I dunno... if i can't build this thing how am I ever gonna build the megasquirt?! ...

 

I think your stim is probably working fine.

It won't get 5v, nor will most of the leds light up until you hook it to the MS.

Ken

 

But I'm trying to do the tach test... where you see if it working correctly by creating a tach signal and hooking it up to an LED to make it blink slower and faster by turning the rpm up and down... no blinky... The test described at the end of the build process here: http://jbperf.com/JimStim/JimStim_v1_4_assembly.html

 

Nothing will blink until it is hooked to the MS.

Ken

 

But it says your supposed to do this test after you build to ensure the jimstim works properly, and you are supposed to do it disconnected from the megasquirt...

Testing the tach signal
If the Jimstim voltage regulator and/or CPU are getting hot when power is applied, refer to the next section (Troubleshooting tach signal, CPU and 3.3V).

Testing of the tach signal can be done using the LEDs. This test will also verify that the Jimstim CPU is working correctly. To do this you need to do this:

Power off the JimStim and disconnect it from the MegaSquirt
Remove the pull up jumpers
Remove the primary tach jumper
Set the wheel mode to distributor mode (all DIP switches off)
Connect a wire jumper from the primary tach header (where the jumper usually goes) to an IAC led. Use the primary tach header pin closest to the pots (away from the PRIMARY TACH text) and the last pin of the 10-pin header (pin closest to the pots)
Connect a wire jumper from the other side of the IAC led to 12V. Use the next to last pin on the 10-pin header (just besides the pin connected in the previous step) and one of the pins on the 3-pin header besides the voltage regulator.
Turn the RPM pots all the way counterclockwise.
Once the connections above are done, power up the JimStim (with the MegaSquirt still not connected) and start slowly turning the RPM FINE potentiometer clockwise. You should see the led start flashing and it will flash faster as you turn the pot more.
Warning: With the JimStim not connected to the MegaSquirt, the bottom of the board will rest on a surface with all the exposed leads and solder pads. Make absolutely sure that the surface is non-conducting and that there is nothing that could make a short also on the surface. A short may cause permanent damage to the CPU and possibly other components.

If the LED does not flash, there is a problem with the JimStim CPU or the board. Go to the next section for troubleshooting. If the LED does flash, the board and CPU are fine. Remove the wire jumpers and put back the needed jumpers before connecting to the MegaSquirt.

To test the second trigger signal, do the same test as above but use the 36-1 wheel mode (only DIP switch #3 on) and connect the LED to the 2nd trigger pin header.

 

Hrrm you may want to ask Jean about that on the msextra forum. I have never had a problem getting my jimstim to work.

Ken

 

Found out the problem. Even though my walwarts output supply to the jimstim was within specs, it still wasn't enough. I was going nuts tracing the schematic and coming up with little theories about what might be bad but it turned out to be a simple fix. Never felt to calming to finally see a little LED blink lol! Next week I'll have to finally put your tips to use and finish the read project here, MS3!

 

Ok, next problem. I finished the build and am trying to connect to the computer for the first time. I have an iMac OS X 10.6.5. I also have windows XP pro SP2 available running virtually via virtualbox. The megasquirt 3 is connected via a USB cable, and finally figured out how to install the FIDI driver stuff for both the mac os x and win xp. I also installed tuner studio on both. But no matter what I do I can't get tuner studio to connect to the mega squirt... Any ideas??

BTW: when I finally do get it connected do I have to load the firmware onto it first?

 

you need to mess with the usb setting. I cant remember exactly what but I know you need to turn one of the setting way down. On a pc you do at the usb port setting. I think!! It has been a long time since I did it last.

 

The MS3 does not come preloaded with firmware. You must load it first.

Ken

 

That was the ticket!! Now were talking to the megasquirt via TS! Thanks for all the help so far You wouldn't happen to have a base tune file for me would ya?

 

I can give you my VE tables and timing tables, you are on your own configuring the unit however.

 

Jobro, are those table for your signature? If so, wouldn't they be to far off? If you think they might work please shoot them to me at imhard@gmail.com Anyone else have a stockish s5 engine tune available?

 

What is your engine specifics?

If you lock timing at 15degrees BTDC and set req_fuel to 8mS for 13B, or 7mS for 12A assuming 550cc primary injectors. And then autofill 60% VE across the board the engine should run *poorly* but that should get you going.

Make sure you use map multiply if the car is turbo. And I still suggest doing it if the car is NA.

 

Stock s5 T2 engine, stock injectors, stock s5 turbo, ... mostly stock lol! For now...

 

2mm mazda apex seals?
Rubber plug corner seals?

Did the rotors have machined bath tubs?

 

My coworker has an S5 T2 that is stock except for the injectors and turbo running ms3 in upgrade mode. I could probably get him to send me his tune.

Ken

 

The motor is a jspec import so I "assume" the apex's are stock 2mm and used the rubber mounts. And I don't think anyone has machined the rotor chambers or changed the compression from a stock s5 t2 in any way...

 

I would appreciate it very much! On a side note, I thought U were running a MS3 as well? Is yours to modded for your tune to be close enough to run mine or something?