[pazi88]

Update 20.5.2021: Rev 2.2 available:https://github.com/pazi88/Speeduino-M5x ... /m52%20PnP

Rev 2.2 PCBs at eBay: https://www.ebay.com/itm/184932328704

Operating instructions for assembled unit: https://github.com/pazi88/Speeduino-M5x ... tions.docx

Assembly instructions available: https://github.com/pazi88/Speeduino-M5x ... tions.docx







There are currently 5 revisions of the M52 PnP Speeduino PCB:

- 1.0: Initial release
- 1.1: Lot of small fixes and adjustments
- 1.2: Additional features like, optional baro sensor, cam sensor input for Hall sensor, CEL light, spare relay outputs
- 1.3: diode for BT module that removes the need to unplug BT module to be able to use USB, A/C circuit with idle up input to mega (this is still the untested one), second external connector that has two more relay output, +5v, GND and serial 3 routed to it.
- 2.0: support for 6-cyl sequential, header for reset control and revised ignition traces.

All the files related to these (BOM, Gerbers etc.) can be found from my Github: https://github.com/pazi88/Speeduino-M5x ... /m52%20PnP

To build one of these m52 PnP speeduinos, you need have the PCB, order components based on BOM and have ms41 ecu to build the speeduino into it because this PCB replaces original one in the ECU case. Instead of to220 insulation pads, you can also try to find slicone adhesive sheets and apply that to the case like this:

This m52 PnP speeduino is pin compatible with the official v0.4 boards, so no special pin mapping needed. There is also m52 Base-tune available here: https://github.com/pazi88/Speeduino-M5x ... /m52%20PnP

In rev1.2 PCB there is also few additions compared to the regular v0.4 pin mapping.
- optional baro sensor is connected to A5
- CEL light is connected to D37
- Spare relay output at external connector is connected to D35, D33 and D31

In rev1.2 and later there is also optional cam input because closed loop VVT control may be thing in some day. This is something that doesn't work directly in M52. You would need to use for example m52tu/m54 intake cam sensor. Or any generic hall sensor. For that there is JP1 jumper that allows the hall sensor to be powered from 12v or 5v. If you for example put this to 12v and replace stock m52 cam sensor with m52tu/m54 intake cam sensor, it will work great. BUT DO NOT USE THAT JUMPER WITH STOCK M52 INTAKE CAM SENSOR. It will fry the sensor or something else.

Other links you might find useful:
- My Speeduino related pics: https://pazi88.kuvat.fi/kuvat/Projektik ... speeduino/
- Rev1.2 project at EasyEDA: https://easyeda.com/pazi88/speeduino-v0 ... m52-rev1-2
- Rev1.1 project at EasyEDA: https://easyeda.com/pazi88/speeduino-v0 ... cb-for-m52


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Hi!

New to this forum, but here's my current contribution to this project. Speeduino v0.4.3 compatible PCB for BMW m52 engines that replaces the original PCB inside the ms41 ecu: https://easyeda.com/pazi88/speeduino-v0 ... cb-for-m52



That's my first bigger PCB design that I have done so feel free to give some feedback, so that I can make some enhancements, before I get those done.

But I also like to get answer if this problem with fuel pump output is solved: https://youtu.be/lfDr_X-hVvE?t=231

I did run into that problem with my real speeduino v0.4.3 board that the fuel pump stays on when laptop is connected to speeduino. Without laptop the output works correctly. If the issue can be fixed in schematic, I would like to do that for my PCB.

[Broke4speed]

I like that a lot.

[curtis12321]

What are you using for ign coil drivers since coils are dumb and oem dme has them built in.

[pazi88]

ISL9V coil drivers. You can see the row on the bottom.

[PSIG]

But I also like to get answer if this problem with fuel pump output is solved: https://youtu.be/lfDr_X-hVvE?t=231

I did run into that problem with my real speeduino v0.4.3 board that the fuel pump stays on when laptop is connected to speeduino. Without laptop the output works correctly. If the issue can be fixed in schematic, I would like to do that for my PCB.

The problem is not in Speeduino or Arduino, but simply that the Arduino is still receiving power through USB or other source. If wanting to shut-down or power-cycle, all sources of power (battery, USB, Ardu-Stim, etc.) must be disconnected so the Mega is fully un-powered. Other convenience solutions exist, such as cutting the USB power cord V+ wire, or removing parts on the Mega, etc.

David

[pazi88]

The problem is not in Speeduino or Arduino, but simply that the Arduino is still receiving power through USB or other source. If wanting to shut-down or power-cycle, all sources of power (battery, USB, Ardu-Stim, etc.) must be disconnected so the Mega is fully un-powered. Other convenience solutions exist, such as cutting the USB power cord V+ wire, or removing parts on the Mega, etc.

David

Yes I noticed that. But other outputs that I tested are not active at that state. Like ignition and injectors. So what makes fuel pump output special? Would the output need like pull-up resistor or something?

[PSIG]

Yes I noticed that. But other outputs that I tested are not active at that state. Like ignition and injectors. So what makes fuel pump output special? Would the output need like pull-up resistor or something?

I'm not sure I follow your logic. What problem does this cause? The Mega is still powered in some way and still running, which it should do if it's powered. If you want to stop the pump while it has RPM input and/or get a key-on pump prime, you must remove all power sources to the Mega so it stops running and resets. The video was quite clear on what combinations results in FP off, FP on, or FP prime and was operating correctly in the video. What scenario would you have where Power + RPM = FP off is desired? This would help determine how to approach a solution to your situation.

David

[pazi88]

I'm not sure I follow your logic. What problem does this cause? The Mega is still powered in some way and still running, which it should do if it's powered. If you want to stop the pump while it has RPM input and/or get a key-on pump prime, you must remove all power sources to the Mega so it stops running and resets. The video was quite clear on what combinations results in FP off, FP on, or FP prime and was operating correctly in the video. What scenario would you have where Power + RPM = FP off is desired? This would help determine how to approach a solution to your situation.

David

No it's enough to just connect usb from mega to PC and fuel pump will run forever, if there is no power to speeduino. No need to engine run or anything.

But last night I did found the cause of the problem. In instructions for uln2003/uln2803 it's adviced to run the com-pin of the chip to the 12v input for the speeduino. But this is a problem, because when there is no 12v input, the uln seems to have enough charge through the coil of the relay (or something?) to turn on the fuel pump relay. But because there is no 12v input in the com-pin the uln can't tunr off fuel pump relay. Also when the relay is really connected and I turn off the ignition, the 12v can still flow through the relay coil and it also goes through the diode in uln to the com-pin. Which is connected to the 12v input of the speeduino and that causes the speeduino not to turn off even when there is no 12v input from car ignition.

The fix for all this was to change the com pin wire from speeduino 12v input to constant battery voltage. And now everything seems to work as it should. Speeduino will shut off when I turn off the ignition and fuel pump only primes when I connect the laptop.

[PSIG]

Also when the relay is really connected and I turn off the ignition, the 12v can still flow through the relay coil and it also goes through the diode in uln to the com-pin. Which is connected to the 12v input of the speeduino and that causes the speeduino not to turn off even when there is no 12v input from car ignition.

Keep in-mind that most OEM and standard wiring does not leave relay coils with live +12V after key-off. This is a function of the key switch or Main relay. This may be a reason you have the issue and most others do not. The easy solution is to place your small relay coil power source onto one of your switched circuits, so Speeduino does not need to be modified, and no live voltage is on Speeduino all the time.

David

[pazi88]

Keep in-mind that most OEM and standard wiring does not leave relay coils with live +12V after key-off. This is a function of the key switch or Main relay. This may be a reason you have the issue and most others do not. The easy solution is to place your small relay coil power source onto one of your switched circuits, so Speeduino does not need to be modified, and no live voltage is on Speeduino all the time.

David

Yes I know but the goal is to make PnP ecu to stock wiring harness that doesn't need modification. And in bmw engine harnesses the ignition switch controls 12v input to ecu and ecu than grounds the fuel pump, main, etc relays that have constant 12v from battery to the other side of the coil. Well not all relays, but still at least one has that 12v coming in all the time.

Of course I could make separate circuitry to control main relay by 12v trigger, but just using fp output for that requires less extra components.

In meantime, I added bluetooth header on the actual m52 pcb, because I now just noticed that it can be used with speeduino also. Maybe it's now time to get those made. Unless I decided add the extra circuitry for the main relay