Megasquirt ON BMW m52 Engine

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maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

jsmcortina wrote:Yes. Connect FUSED 12V to pin 28 and ground to any of the ground pins.

James
thanks, i did it :yeah!: successfully connected with tunerstudio on com port.



but still cant complete wiring diagram. :cry: no one has m52 engine with ms3x?
hassmaschine
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Re: Megasquirt ON BMW m52 Engine

Post by hassmaschine »

if you want to use all stock wiring you'll need to build a relay circuit like this one:
http://www.megasquirt.325ix.com/MS_to_M ... rcuit.html

I've only half started the M52 wiring chart so I don't have the equivalent pinouts (mine is for an M50 vanos).. but basically: the ignition switch sends a signal to the ECU, the ECU turns on the main relay. The main relay powers the ECU and all the engine electronics. Everything is already fused.

I have a friend who's also added a capacitor to this circuit because he found voltage drops were shutting off the circuit making it look like synch loss. I'll have to talk to him and add it to my diagram, although I haven't had this problem. BMW is using a capacitor on the stock circuit, though.

what specific questions are you having with your wiring?
maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

hassmaschine wrote:if you want to use all stock wiring you'll need to build a relay circuit like this one:
http://www.megasquirt.325ix.com/MS_to_M ... rcuit.html

I've only half started the M52 wiring chart so I don't have the equivalent pinouts (mine is for an M50 vanos).. but basically: the ignition switch sends a signal to the ECU, the ECU turns on the main relay. The main relay powers the ECU and all the engine electronics. Everything is already fused.

I have a friend who's also added a capacitor to this circuit because he found voltage drops were shutting off the circuit making it look like synch loss. I'll have to talk to him and add it to my diagram, although I haven't had this problem. BMW is using a capacitor on the stock circuit, though.

what specific questions are you having with your wiring?
i used this diagram: http://www.megasquirt.325ix.com/MS_to_M ... 3.3.1.html
and this http://www.msextra.com/forums/viewtopic ... 31&t=37175
i've changed ecu pin numeration according to ms41.1 (diagram on first page)
but it needs doublecheck and completion of rows with "???" record. i dont know maybe i dont need them at all
if you have any other diagram, please share to compare with

and one question about cirquit

there's written that
2 The Base connect to pin 56 with a 7.5k ohm resistor

but according to this link http://www.megasquirt.325ix.com/MS_to_M ... 3.3.1.html
56pin goes go to 29 mainboard

and one more question

VB921 transistor is installed within the ECU and needs to change with BIP373 yes?


p.s

i'm not familiar with resistors transistors and so on... its a real headache :lol:
hassmaschine
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Re: Megasquirt ON BMW m52 Engine

Post by hassmaschine »

29 on the main board is just an open pin. you could use any of the 4 open IAC pins on the DB37, or SPR1-4. Their selection is arbitrary. the IAC pins aren't connected to anything unless you jumper them somewhere - since I'm not using the stepper IAC hardware (using the MS3x 3 wire PWM IAC support), I used those pins for the relay circuit.

my diagram is based off the Motronic ECU, your M52 has a Siemens ECU and uses a different pinout. Also, I built it to use on an M20, which is why things like the VVT pin are used for other purposes (since VVT is just a generic PWM output). Just be careful that you aren't copying my Motronic 3.3.1 diagram for a Siemens MS41 harness. The functions are the same, but the pin locations aren't.

also, I believe you need to change the cam sensors to a hall type, the cam sensors on the M52 are some sort of hybrid sensor that as far as I know, MS doesn't support.

as far as the VB921s - are you using the mainboard outputs? why not use the MS3x outputs? you'll have to add 6 coil drivers either way. BIP373s are prefered over VB921s, but you could use the VB921 of course. it's just not as reliable.
maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

hassmaschine wrote:29 on the main board is just an open pin. you could use any of the 4 open IAC pins on the DB37, or SPR1-4. Their selection is arbitrary. the IAC pins aren't connected to anything unless you jumper them somewhere - since I'm not using the stepper IAC hardware (using the MS3x 3 wire PWM IAC support), I used those pins for the relay circuit.
ok, thats clear
hassmaschine wrote:my diagram is based off the Motronic ECU, your M52 has a Siemens ECU and uses a different pinout. Also, I built it to use on an M20, which is why things like the VVT pin are used for other purposes (since VVT is just a generic PWM output). Just be careful that you aren't copying my Motronic 3.3.1 diagram for a Siemens MS41 harness. The functions are the same, but the pin locations aren't.
yes, i've found wiring diagram for siemens 41.1 on a website you wrote on a first page and changing pins according to it.
hassmaschine wrote: also, I believe you need to change the cam sensors to a hall type, the cam sensors on the M52 are some sort of hybrid sensor that as far as I know, MS doesn't support.
m50 cam sensor will be ok yes?
hassmaschine wrote: as far as the VB921s - are you using the mainboard outputs? why not use the MS3x outputs? you'll have to add 6 coil drivers either way. BIP373s are prefered over VB921s, but you could use the VB921 of course. it's just not as reliable.
i use ms3x outputs. like on your motronic to ms3x diagram

can i use stock coil drivers? i've found them in stock 41.1 ECU. "STP8055" by motorola


and some more question i have about wiring, and almost done.

so this is siemens 41.1 wiring diagram

Image
Image
Image

1) cant find "FP relay, Terminal 85" pin "1 37 Brown/Green FP relay, Terminal 85 FP FP/O2"
2)also cant find oxygen sensor signal pin. "13 23 Yellow O2 sensor input O2"
3)i got 2 camshaft position sensor on diagram. pin 43 and pin 65 :?:
4)oxygen sensor heater control missed "38 37 Brown/Green O2 relay, terminal 85 FP"
5)vehicle speed signal "42 29x Black/White VSS - from cluster N2O IN Can also use MS3x spare ADCs as inputs 12v or GND switched input"
6)5v component supply "59 26 Red/Yellow TPS +5v Vref (5v)"



big thanks for helping
justnsk
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Re: Megasquirt ON BMW m52 Engine

Post by justnsk »

hassmaschine wrote:if you want to use all stock wiring you'll need to build a relay circuit like this one:
http://www.megasquirt.325ix.com/MS_to_M ... rcuit.html
I have a friend who's also added a capacitor to this circuit because he found voltage drops were shutting off the circuit making it look like synch loss. I'll have to talk to him and add it to my diagram, although I haven't had this problem. BMW is using a capacitor on the stock circuit, though.
Can you please specify where exactly should this capacitor be and a size of it? I am building an adaptor for my m50 wiring loom and also for my friends m20 using "start cirquit" descriptions from Chris325ix and Ryan Nimick
hassmaschine
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Re: Megasquirt ON BMW m52 Engine

Post by hassmaschine »

man, I typed out a LONG reply with detailed answers to your questions yesterday, and the power went out in the office just as I was going to hit send. :x

as far as the cap - I don't know, I'd have to ask, but it doesn't have to be very big - just enough so that the relay doesn't shut down due to noisy voltage.
hoveringuy
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Re: Megasquirt ON BMW m52 Engine

Post by hoveringuy »

Here's how I did it:
Megasquirt power.jpg
maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

noone? :cry:
can i use stock coil drivers? i've found them in stock 41.1 ECU. "STP8055" by motorola
hassmaschine
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Re: Megasquirt ON BMW m52 Engine

Post by hassmaschine »

yes, you can, just build an external box and make sure they're heatsinked. might also want to check what bias resistors are being used by the stock ECU. you can trigger them off the MS3x coil outputs.
maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

hassmaschine wrote:yes, you can, just build an external box and make sure they're heatsinked. might also want to check what bias resistors are being used by the stock ECU. you can trigger them off the MS3x coil outputs.
good :) thanks

and cant find VVT settings in TunerStudio advanced engine section. why? :shock:

can i take ground from db37 to my old ecu box with 1 cable and then spread on Siemens ecu Pins? or better separate cables on each pin?
hassmaschine
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Re: Megasquirt ON BMW m52 Engine

Post by hassmaschine »

all the pins on the top row are grounds except for 3-4-5-6 (the SPR pins). I would use as many as you can.
jsmcortina
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Re: Megasquirt ON BMW m52 Engine

Post by jsmcortina »

maxo-tt1 wrote:and cant find VVT settings in TunerStudio advanced engine section. why? :shock:
The manual page has the answer:
vvt manual page wrote:Note! This feature is only available in 1.1 alpha codes
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

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maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

jsmcortina wrote:
maxo-tt1 wrote:and cant find VVT settings in TunerStudio advanced engine section. why? :shock:
The manual page has the answer:
vvt manual page wrote:Note! This feature is only available in 1.1 alpha codes
James
sorry but what that means? 1.1 alpha code of what?

so i cant use vvt? :o
prof315
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Re: Megasquirt ON BMW m52 Engine

Post by prof315 »

V1.1x alpha code is the the current test code that has all of the newest features in it including VVT. The current version right now is 1.18. It is however TEST CODE and as such you use it at your own risk. That being said I have been running alpha code on all of my MS3 projects from day one with only a couple of issues in the earlier versions.
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maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

prof315 wrote:V1.1x alpha code is the the current test code that has all of the newest features in it including VVT. The current version right now is 1.18. It is however TEST CODE and as such you use it at your own risk. That being said I have been running alpha code on all of my MS3 projects from day one with only a couple of issues in the earlier versions.
and how to get this alpha code? i have to download if from somewhere or? please some more hint :(

i've searched the net but found nothing
jsmcortina
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Re: Megasquirt ON BMW m52 Engine

Post by jsmcortina »

Search this forum and you'll find it.
Or go to the MS3 developement subforum and it is the first post.
http://www.msextra.com/forums/viewforum.php?f=125

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

thanks james :)


wiring almost done :) some sensors left and will start :yeah!:

Image
maxo-tt1
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Re: Megasquirt ON BMW m52 Engine

Post by maxo-tt1 »

hello people...

have one problem about start circuit.. i use my siemens wiring, and reley are different. can someone help me modify diagram above ?

that diagram says that on bosch relay 30 and 86 are battery voltage.

on my siemens reley i got voltage in only 87

this is my reley... maybe someone know how to remake it ? :(
jsmcortina
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Re: Megasquirt ON BMW m52 Engine

Post by jsmcortina »

Can't you just wire it up in the normal way like in the manual ?

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
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