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BMW M3 S50B32 Wiring G4 Extreme

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Hi I was wondering if anyone can help me out and see if my wiring pin out is correct. I have attached my wiring chart I made to make my own PnP to the factory engine harness along with the factory ECU pinout and their functions. I have a red box G4 Extreme with CAN port.

I have a BMW M3 with S50B32 but I will be adding an ethanol content sensor for now as I would like to tune the car to run E85 on 600CC injectors while I put together parts for a turbo build as I will be adding a boost controller and probably an anti lag switch.

Am I fine running the factory dual narrow band sensors or should I get an Innovate LC-2 and place it on the 3-6 cylinder bank exhaust manifold or would I want to run dual lambda controllers over CAN?

 

Link Wiring .xlsx

MSS50.pdf

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I have made some changes.  I highlighted all my changes in red.  

Note only aux 1 & aux 2 are capable of driving a 3 wire idle valve but with this engine aux 1 & 2 are needed for the vanos.  The workaround for this is an external circuit to make the idle valve work more like a two wire version which can then be connected to any of the spare auxes.  I will attach a diagram for that below.

Note the G4 doesnt work with CAN bus lambda controllers, only analog.  

 

Adams notes.xlsx

3 Wire ISC with 1 Aux.pdf

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5 hours ago, Adamw said:

I have made some changes.  I highlighted all my changes in red.  

Note only aux 1 & aux 2 are capable of driving a 3 wire idle valve but with this engine aux 1 & 2 are needed for the vanos.  The workaround for this is an external circuit to make the idle valve work more like a two wire version which can then be connected to any of the spare auxes.  I will attach a diagram for that below.

Note the G4 doesnt work with CAN bus lambda controllers, only analog.  

 

Adams notes.xlsx

3 Wire ISC with 1 Aux.pdf

So I would be making a jumper wire from Pin 54 on the ECU connector to Pin 27 or do I leave them alone as I also use the M50 PnP pinout as reference with no mention for those equivalent pins. Pin 54 is the +14V activated by the ignition switch for both.

Can I auto tune on narrow band sensors or I need a wideband and controller to use it?

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20 hours ago, token said:

So I would be making a jumper wire from Pin 54 on the ECU connector to Pin 27 or do I leave them alone as I also use the M50 PnP pinout as reference with no mention for those equivalent pins. Pin 54 is the +14V activated by the ignition switch for both.

You have pin 54 correct in the xlsx I attached, this is the main power supply to the ECU from the main relay.  You need to ground Pin 27 to make the main relay energise it.  On our plug-in ECU we have an extra circuit (mosfet) to do this, you can use a relay controlled by pin 56 like below to ground pin 27 when ignition switch is turned on.

 

CwjOWPY.png

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On 10/4/2018 at 11:57 PM, Adamw said:

You have pin 54 correct in the xlsx I attached, this is the main power supply to the ECU from the main relay.  You need to ground Pin 27 to make the main relay energise it.  On our plug-in ECU we have an extra circuit (mosfet) to do this, you can use a relay controlled by pin 56 like below to ground pin 27 when ignition switch is turned on.

 

 

Can a 2n2222a transistor be used for the relay? Base to Pin 56, emitter to ground, and collector to pin 27?

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14 hours ago, token said:

Can a 2n2222a transistor be used for the relay? Base to Pin 56, emitter to ground, and collector to pin 27?

In theory it would work, but I'm not sure that would be happy with the kickback from the main relay and various other transient surges that are common in the automotive environment.  In our E36 plugin ECU for instance the Mosfet that we use for switching this main relay is rated at 60A, 55V.  

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2 hours ago, Adamw said:

In theory it would work, but I'm not sure that would be happy with the kickback from the main relay and various other transient surges that are common in the automotive environment.  In our E36 plugin ECU for instance the Mosfet that we use for switching this main relay is rated at 60A, 55V.  

I have found this as a reference for a M50 wiring guide to make a Megasquirt 3 PnP which seems to work. Or I can order the same Mosfet used in the plugin so I can put all the electronics components I need into one order and solder everything to the header.

322751392_startercircuit_zps7qqfpo2l.thumb.png.5bd29e84cc2655d6ac678c3ad186230d.png

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16 minutes ago, token said:

I have found this as a reference for a M50 wiring guide to make a Megasquirt 3 PnP which seems to work. Or I can order the same Mosfet used in the plugin so I can put all the electronics components I need into one order and solder everything to the header.

I would go with that circuit you have above since it sounds like it is working for someone else.  Im not authorised to give out our internal schematics and I dont have enough experience of what voltages and other scenarios we need to account for to make a better suggestion myself (apart from my original relay suggestion above).   Remember to allow for situations such as someone connecting the battery reverse polarity etc.

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