OhBilly Posted July 14, 2011 Share Posted July 14, 2011 I just finished building a new MS1, V3.0 and have got it installed in the car per the instructions in the install article on DIYAutoTune (I'm using the relay board): I am attempting to download the MSnS-Extra firmware to the ECU but I'm not getting very far. After shorting the bootloader pins and turning on the ignition to supply +12V power, I'm getting an error basically saying Expecting "boot>", Received " " once the download attempts to start. I've done a bit of research trying to figure out the reason, and one thing I came across is someone mentioning that this issue is seen when you are not supplying +12V to pin 24, or in my case since I am using the relay board, connection #15 in the above schematic (TACH line) on the relay board. With the ignition on and bootloader pins shorted, I checked the voltage at this connection and sure enough, it reads in the millivolt range, not even close to +12V. I couldn't realize how this could be until I remembered that there's a 1K ohm resistor between my switched +12V source and the TACH line, per the DIYAutoTune instructions. If I check the voltage prior to the resistor, I do indeed read about +12V (I don't remember exactly, but I think it read about 11.5V). Now, the question is, should I be shorting that 1K ohm resistor in order to get the firmware to download? If this would work, would doing so cause any damage to the distributor ('83 turbo dizzy) if it gets a full +12V rather than the millivolts it would be getting with the 1K ohm resistor inline? Of course it's easy enough to disconnect the connection to the distributor if needed, but I'd rather not do it unless I need to. Thanks for any advice, Bill Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 14, 2011 Share Posted July 14, 2011 Pin 24 is the tach input trigger. You do not need 12 volts on this pin to program firmware. You do need 12 volts to power up megasquirt which comes in on pin 28. If you have 12 volts on pin 28 you should be able to load firmware regardless of pin 24 being at basically zero. When you turn the key on, then one of the relays will switch on and it provides 12 volts to power the MS board through pin 28 of the DB37 connector. Quote Link to comment Share on other sites More sharing options...
OhBilly Posted July 15, 2011 Author Share Posted July 15, 2011 Thanks moby, that helps... and it makes sense. The poster must have got his pin numbers mixed up. The MS box is getting power for sure because if I power it up without the boot loader pins shorted, the ECU comes to life: the fuel pump primes for a few seconds, and the LEDs on the MS box light up (IIRC, one light blinks for a moment and then the middle LED lights up solid and stays that way). If I keep power going to the MS box this way, after about 10 seconds or so, the relays start chattering like crazy. Should any LEDs light up when the bootloader pins are shorted? If so, I don't get any. Is there anything else that I should be checking? If I can't get it to work, I'll likely send it off to DIY for troubleshooting. Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted July 21, 2011 Share Posted July 21, 2011 Try using the bootloader jumper when you get that message - 9 times out of 10, that gets the code loaded. Quote Link to comment Share on other sites More sharing options...
BLOZ UP Posted July 22, 2011 Share Posted July 22, 2011 I can never get mine to upgrade without enabling debug output. Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted July 22, 2011 Share Posted July 22, 2011 I can never get mine to upgrade without enabling debug output. Debug output slows down communications and can help loading firmware when you have serial noise issues. It can be worth a try, but I don't think the OP got far enough to where this has an effect. Quote Link to comment Share on other sites More sharing options...
OhBilly Posted August 5, 2011 Author Share Posted August 5, 2011 Try using the bootloader jumper when you get that message - 9 times out of 10, that gets the code loaded. Matt, I am jumpering the bootloader contacts for my attempts, but maybe the way I've done it is part of the problem: To avoid having to remove the case cover, I soldered wires to the bootloader contacts (1 wire each) and routed them outside the case. To jumper the contacts, I simply twist the ends of these wires together. I don't see any reason why this wouldn't work, unless the wire lengths are too long and there's too much resistance in them. Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted August 5, 2011 Share Posted August 5, 2011 Or there could be a faulty solder joint at the boot jumper... Quote Link to comment Share on other sites More sharing options...
OhBilly Posted October 5, 2011 Author Share Posted October 5, 2011 I'm looking for someone who can physically troubleshoot and repair this board. Any takers? I can ship the board out to you and of course, pay you for your time and materials. I just don't have the time and skills to do it myself. I'm working in the Aurora, IL area and living near Joliet, IL if anybody is close enough to avoid having to ship. Thanks, Bill Quote Link to comment Share on other sites More sharing options...
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