z-ya Posted February 2, 2009 Share Posted February 2, 2009 I remove the MSII daughter boards using a small screwdriver. I very lightly pry on the heatsink end, just a little. Then move to the other end. Before powering it up, check for shorts between 12v and ground, and from 5V to ground. Or, if you have a power supply with current limiting, set it to 150mA or so and watch the power supply voltage. Also, I would reflow every solder joint as well. Sounds more and more like a real hack put this one together. Pete Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted February 2, 2009 Share Posted February 2, 2009 I suspect that someone shorted a 12 volt connection to the VREF wire; this is the most common cause of dead D19s. Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 2, 2009 Share Posted February 2, 2009 Hey Pete, Normally I would just lightly pry it up from the ends with a screw driver. Unfortunately, this one doesn't want to give at all. Tonight I think I'm going to reflow the solder around the socket pins and hopefully the heat will break the daughter board pins free a bit so I can get it up. I don't think the person that put it together is the problem. I'm starting to think it's the previous owner that didn't know what he was doing and once he realized he did more damage than he could repair, he chucked it off on ebay. Unfortunately our friend junglist was taken by this guy. Fortunately however he didn't pay much for it. Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 2, 2009 Share Posted February 2, 2009 Hopefully I won't have to replace the entire injector output circuit in this thing. Granted the parts are cheap, but I hate replacing those little transistors, I need Asian hands and better eyes for those little pins, lol. Quote Link to comment Share on other sites More sharing options...
Matt Cramer Posted February 2, 2009 Share Posted February 2, 2009 I need Asian hands and better eyes for those little pins, lol. Sony - because Caucasians are too damn tall! Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 2, 2009 Share Posted February 2, 2009 Sony - because Caucasians are too damn tall! Haha! Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 3, 2009 Share Posted February 3, 2009 Ok this thing is driving me insane. I'm going to have to desolder the whole processor socket to get it out. No idea what I'm going to do from there, but I'll figure something out. I might drop the proc in my MS to see if it works or not. Fortunately I have good DMM again to check things over with. Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 17, 2009 Share Posted February 17, 2009 Can someone explain to me...please...why when there is a 40 pin socket in the kit you would SOLDER THE PROCESSOR STRAIGHT TO THE DAMNED CIRCUIT BOARD!?!?!?!?! Quote Link to comment Share on other sites More sharing options...
z-ya Posted February 17, 2009 Share Posted February 17, 2009 Can someone explain to me...please...why when there is a 40 pin socket in the kit you would SOLDER THE PROCESSOR STRAIGHT TO THE DAMNED CIRCUIT BOARD!?!?!?!?! In the case of high speed design (which this isn't), sockets are not acceptable as they introduce too much capacitance. In this case there is no reason besides stupidity. Or, they didn't buy the kit and omitted the socket from the BOM to save money (again, stupidity). Pete Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 17, 2009 Share Posted February 17, 2009 In the case of high speed design (which this isn't), sockets are not acceptable as they introduce too much capacitance. In this case there is no reason besides stupidity. Or, they didn't buy the kit and omitted the socket from the BOM to save money (again, stupidity). Pete That's what I figured. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted February 17, 2009 Share Posted February 17, 2009 There is one real reason I have seen for not using sockets, but I don't think it would apply to the megasquirt. If you look at old circuits that have been run for 20-30 years the pins of the parts put in sockets corrode and the parts have to be replaced. The parts soldered on the board do not have this problem. I notice this on arcade and pinball machines from the late 70's and early 80's. The arcade machines were probably powered on 24/7 for a few years of their life. Maybe when you have run an MS unit in your car for over 20 years the socket may be unreliable Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 17, 2009 Share Posted February 17, 2009 I have to wonder if this MS unit has ever worked properly. The amount of damage I've seen on this board suggests it's had problems from assembly on. Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 27, 2009 Share Posted February 27, 2009 Ok, long series of events here. I was almost going to give up on this thing. First, after removing the proc I found more broken traces on the board. Frustrating....very frustrating.. I replaced the traces with pieces of wire strand (carefully with tweezers). Once that was done I installed a 40 pin socket for the CPU, repaired a broken pin on the CPU and replaced U4 and D19. I put the proc in my MS box and fired it up on the stim. Everything looked good. I put it back in the original box, firred it up and everything looked the same. The only thing I didn't like were that the warm up and accel enrichment LEDs didn't seem to work right. Right now I'm trying to upload new firmware to it and see if I can get it configured and working properly in MegaTune. Wish me luck. Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 27, 2009 Share Posted February 27, 2009 Done! She's loaded, verified and ready to run. Quote Link to comment Share on other sites More sharing options...
junglist Posted February 27, 2009 Author Share Posted February 27, 2009 Jeremy has helped me out a lot looking into this for me and getting this thing up and running. I owe all you guys a lot of thanks. Quote Link to comment Share on other sites More sharing options...
naviathan Posted February 27, 2009 Share Posted February 27, 2009 Jeremy has helped me out a lot looking into this for me and getting this thing up and running. I owe all you guys a lot of thanks. I'm just glad I could help. It was looking pretty bad for a bit there and I was starting to wonder if I would be able to pull it off, but all turned out well. You will have your MS back next week. Thanks for your patience through all this. Quote Link to comment Share on other sites More sharing options...
RB240z Posted March 2, 2009 Share Posted March 2, 2009 Jeremy, Thanks so much for your time, patience and persistence. We owe you a ride when the car is finished, and of course, some beers! -Ryan Jeremy has helped me out a lot looking into this for me and getting this thing up and running. I owe all you guys a lot of thanks. Quote Link to comment Share on other sites More sharing options...
naviathan Posted March 2, 2009 Share Posted March 2, 2009 Jeremy, Thanks so much for your time, patience and persistence. We owe you a ride when the car is finished, and of course, some beers! -Ryan Sounds good to me. I've never been one to turn down barley and hops! Again I'm just glad it worked out well in the end. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.