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For what ever reason I cannot get my megasquirt to power up in the car. I have plugged a 12v dc adapter into it and it fires up and i can connect to it but once in the car I get nothing. I checked pin 18 and I'm getting constant power, I've checked all the ground they are good. I checked pin 36 and its seeing main relay output of source voltage says its a brown wire is that supposed to be a ground?? I checked pin 37 which is supposed to be switched ignition power but I'm not seeing any power there. I pulled the main relay and swapped in another to no avail. While the relay was out I had source power on two of the pins but not on the center pin which is the red/blue wire that goes to pin 37 so it seems that the relay isnt transferring the current over. My battery is kind of low as the car was sitting for a few weeks showing like 11.4v should i try charging it up and seeing if that does it? Does MS or the relay need to see a min of 12 volts to switch over?

Best try verifying you have proper voltage. I don't think 11.9 is enough for the car to start/crank .

I got it figured out sorta. Charged battery over night. Put it back in the car still nothing so i put the stock ecu in and everything works as it should so i can safely assume my harness is good but something in the MS unit is not. Is there a “wake up” setting i need to make in tuner studio? Im also going to be checking all the joints and wiring. Its a pre built unit from SSSquidtuning.

Might be worth getting with Jay at sssquid... You do need to make sure your laptop has the proper software and firmware as well as baud rate settings, but I believe it should recognize or power up if all was correct from the getgo.

tschultz wrote: Jun 01, 2020 11:32 AM Might be worth getting with Jay at sssquid... You do need to make sure your laptop has the proper software and firmware as well as baud rate settings, but I believe it should recognize or power up if all was correct from the getgo.

Yea when i plug the 12v dc adapter into the ms unit. It will connect to the laptop and i can make adjustments. It just wont power up in the car. I emailed him waiting for a response. I noticed pin 37 on my bored has nothing on it?

I put a jumper wire on the main relay connector from terminal 30 to 87 on main relay connector when I did this the MS unit powered on since terminal 30 is always hot the key wasnt needed on. So this tells me that pin 37 on the board is not getting power which in turn powers the rest of the board. A thought I had but I'm unsure of, is take a wire for the second pin 27 terminal on the 55 pin adapter board and wire it one of the three 12v inputs on the board it self. One of the inputs already has a wire going from it to pin 37 however its clear voltage isnt getting that far. So maybe pin 27 to the 12v input would then send power to pin 37 activating terminal 87 on the main relay allowing it to turn on or would it just instantly turn on once power hits it from pin 27 rendering pin 37 useless.

Are you checking pin 37 directly on your MS box?
What harness are you running?
Know good?
Custom built, stock or hack job by someone?
Are you running a Bosch 55 > DB37 adapter to convert?

If you're getting +12v & -12v at the correct terminals, then I'd circle back to the MS box.

On your Megasquirt implementation, do you have a main relay control circuit?
See the drawing at the link below:
http://www.magicview.ro/mye28/microsqui ... ontrol.pdf
Note that my project was for a car with wiring harness specific to Motronic 1.3. But the principle is the same, you just have to be careful about pin numbers.

Here's the thread of my project, maybe you can find some other hints that may help:
https://www.bimmerforums.com/forum/show ... my-E32-M30

Nebraska_e28 wrote: Jun 03, 2020 12:13 AM Are you checking pin 37 directly on your MS box?
What harness are you running?
Know good?
Custom built, stock or hack job by someone?
Are you running a Bosch 55 > DB37 adapter to convert?

If you're getting +12v & -12v at the correct terminals, then I'd circle back to the MS box.

Yes I have power to pin 37 at the MS box. IT is a custom built 55 pin unit done by a professional and everything I'm looking over appears correct. I'm running a 1.3 harness out of a auto e34 as it has the 6 pin tps but I removed all the random auto bs for the harness that wasnt needed and car works with stock ecu

RobertRO wrote: Jun 03, 2020 3:30 AM On your Megasquirt implementation, do you have a main relay control circuit?
See the drawing at the link below:
http://www.magicview.ro/mye28/microsqui ... ontrol.pdf
Note that my project was for a car with wiring harness specific to Motronic 1.3. But the principle is the same, you just have to be careful about pin numbers.

Here's the thread of my project, maybe you can find some other hints that may help:
https://www.bimmerforums.com/forum/show ... my-E32-M30

yes i have a relay control circuit. ppin 27 is relay in on the relay 2 part of board. pin 36 is relay out. pin 37 goes to the 12v section on the board it all has power like it should. I did notice though only my pin is a ground. rest are not going to a GND portion on the board

Im not entirely sure if this is related but i remember when converting to m1.3 with a e34 harness some of the relays were ground triggered or vice versa and i had to do some rewiring . It was awhile ago but the point is i would make sure you know exactly what is controlling the relays and whether it is doing it via a ground or 12v signal.

mitch5 wrote: Jun 03, 2020 12:05 PM Im not entirely sure if this is related but i remember when converting to m1.3 with a e34 harness some of the relays were ground triggered or vice versa and i had to do some rewiring . It was awhile ago but the point is i would make sure you know exactly what is controlling the relays and whether it is doing it via a ground or 12v signal.

relays is controlled via 12 signal. I confirmed this when jumping power from one of the terminals I think 30? that has constant power to the center terminal which goes to pin 37 I jumped power across to it and the unit turned on. I checked pin 37 on the ms unit with the key on and it is getting power so I'm wondering if i dont need a ground somewhere cause its getting power but not knowing what to do with it. I will have to see if when its getting power at 37 if im seeing it at the terminal on the relay. forgot to do that last night

its fixed. was a bad ground from pin 2 to the ground pins on the ms board

Nice!
I was 3 weeks trying to figure out why I didn't have a pulse signal.
Good luck with the tune.

With my B35 auto harness from a E32, I had to rewire my coil wire to the main relay so my car would shut off after the key was turned off. That's the only wiring change I had to make for the MSPNP2