RPM not synced
#25
OK, constructive criticism time here...
I have only ever built a DIYPNP, and never a MS3X. I'm not familiar enough with the circuitry to spot an obvious mistake. Having said that, I have professionally soldered PCB's before, and I see a lot of issues with your soldering job. It's always a little tough to tell in a photo what's solder and what's just camera flash off of flux, but it looks to me like you've got solder bridges across some locations (3 prong- guessing transistors?). You also have a lot of cold sockets.
My recommendation is that you get a decent soldering iron with adjustable temperature and a fine soldering tip. You may also want to buy some small side cutters for trimming leads, and a solder sucker for removing solder. When you reheat a socket, you'll need to flow a little more solder into it to make it join. It's not so much the extra solder as the extra flux that's helping to make the bad join good. Spend a few minutes on YT reviewing a good "how-to" video. You need to be able to tell by looking at the leads whether you got a good flow of solder or not.
Also, one of your pics looks like you have a torn trace on the PCB. I can't tell if the yellow wire is there as a repair?
I have only ever built a DIYPNP, and never a MS3X. I'm not familiar enough with the circuitry to spot an obvious mistake. Having said that, I have professionally soldered PCB's before, and I see a lot of issues with your soldering job. It's always a little tough to tell in a photo what's solder and what's just camera flash off of flux, but it looks to me like you've got solder bridges across some locations (3 prong- guessing transistors?). You also have a lot of cold sockets.
My recommendation is that you get a decent soldering iron with adjustable temperature and a fine soldering tip. You may also want to buy some small side cutters for trimming leads, and a solder sucker for removing solder. When you reheat a socket, you'll need to flow a little more solder into it to make it join. It's not so much the extra solder as the extra flux that's helping to make the bad join good. Spend a few minutes on YT reviewing a good "how-to" video. You need to be able to tell by looking at the leads whether you got a good flow of solder or not.
Also, one of your pics looks like you have a torn trace on the PCB. I can't tell if the yellow wire is there as a repair?
#26
Yea this is the first pcb i've soldered before so that's to be expected. For the transistors i'm quite certain they aren't bridged, as i've taken a really close look to make sure of that before but those are quite the bitch to get right so i'll take another look. The yellow wire is to replace the broken trace.
#31
If it was me, I'd try either a known good CAS while running on the ms3, or try disconnecting the crank signal wire while running on the factory ECU. If a known good CAS makes the ms3 work, it was a bad CAS. If disconnecting the crank signal wire while running the OE ECU DOESN'T make a difference, you know it's a problem with either the CAS or crank wiring in the harness, but the OE ECU doesn't care.
But again, looking at those pics of the ms3, my gut is a bad solder join that needs some love.
#33
I went over and desoldered/resoldered most of the connections last night and they definitely look a little better but every point looks connected. I noticed i missed a capacitor on c23 and put that in and gave another test start but still no rpm. I also noticed i omitted the A/C in and out wires because my car has no A/C but do these wires have a different use?
#36
I had the exact same issue last year, and your composite log looks identical to mine (other than the rising/falling edge difference):
yours:
mine:
I had to adjust my R54: https://www.miataturbo.net/megasquir...0/#post1355522
hopefully it's as simple as that for you too.
yours:
mine:
I had to adjust my R54: https://www.miataturbo.net/megasquir...0/#post1355522
hopefully it's as simple as that for you too.
#37
I had the exact same issue last year, and your composite log looks identical to mine (other than the rising/falling edge difference):
yours:
mine:
I had to adjust my R54: https://www.miataturbo.net/megasquir...0/#post1355522
hopefully it's as simple as that for you too.
yours:
mine:
I had to adjust my R54: https://www.miataturbo.net/megasquir...0/#post1355522
hopefully it's as simple as that for you too.
#38
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the two transitors on the bottom of the board. q22 and q24 iirc, is the solder bridging the leads?
without seeing your composite log they looked suspect, and i bet that's the issue (if the pot resistor is actually tuned 7.5 turns CW)
without seeing your composite log they looked suspect, and i bet that's the issue (if the pot resistor is actually tuned 7.5 turns CW)