slow_hemi6 wrote:I hope you noticed the numbering on the female plug runs backwards. The photo shows your leads across pins 19 and 33.
Yeah I flipped it after that pic. Thats how I checked it though. I checked voltage at the sensor. And have the same reading on the other end at the plug. The plug was already on the wires so I know they're where they need to be. It's either the settings or the board. I've started going over everything and redid the voltage checks on the cpu socket which all came back right as well. My concern now is that something on the board isn't right or something fried.
Continued to check things. Powered the stim up and did a multimeter test on the resistor next to it and got it down to .553 volts where it stopped going down. Plugged it back in the car. Still no signal
billr wrote:Do you still get rpm and sync when using the stim, with "basic trigger" set in TS?
What ACV do you get out of the good (cam) VR sensor, when put in the CKP position and cranking?
I have no clue what resistor you are referring to in the previous post; what number is it on the schematic?
Its not a steady RPM now. Its pretty erattic. Like it will jump to around 1000 RPM. then from there jump straight to around 5600. Then redline. then drop back to 0. and it does it really quickly. Faster then I'm turning the knob. The ACV fluctuates a lot on the sensor but its a steady fluctuation back and forth between very similar numbers. I would have to do it again to get the exact numbers. And its R54 on the schematic.
So I have an internal problem on my build. I found the article on bench testing the VR circuit.
I soldered a wire to pin 24. Did a continuity check with a lead stuck in the 24 pin on the connector to find the correct spots. Im not sure where to get 5V from so I grounded the wire on the heat sink. And according to this I should have between 0 and .7 volts on pin 2 of U7. Is this good?
So Im discovering a DIY ECM brings a whole new level to the meaning of DIY with the level of leaving you to figure it out for yourself. I cant believe how shitty tech support for this company is after the amount of money spent for all this stuff.
billr wrote:Let me know if/when you are done with the temper-tantrum. I don't want to waste time trying to help further until then.
Sorry if you feel that was directed at you. I emailed in about this issue last week. The forum is more help and I've gotten really no where further then knowing my wiring is sending a signal.
If you build the boards yourself, you have to take the responsibility for the build quality.
Are you saying that with pin24 grounded you are seeing 2.5v on pin2 of u7 and then with 5v on pin24 you are still seeing 2.5v on pin2 of U7? ie No change?
If you are applying 5v to pin 24 and not seeing 4 or more at pin2 of U7 then there is an issue. With the 5v applied what voltages do you measure on each side of R44 and each side of R48?
Check the carefully the soldering of Q22.
Find the Manuals up top under Quick links: Manuals.
Cheers Luke
slow_hemi6 wrote:If you build the boards yourself, you have to take the responsibility for the build quality.
Are you saying that with pin24 grounded you are seeing 2.5v on pin2 of u7 and then with 5v on pin24 you are still seeing 2.5v on pin2 of U7? ie No change?
If you are applying 5v to pin 24 and not seeing 4 or more at pin2 of U7 then there is an issue. With the 5v applied what voltages do you measure on each side of R44 and each side of R48?
Check the carefully the soldering of Q22.
I've been convinced since it didnt work the first time that i built it wrong. So Im not blaming anyone for it not working. Yes the voltage was off. The joints looked good on Q22. There was a clean break between each leg not connecting them. That doesn't mean I didn't fry it when trying to get things to work. So I desoldered it and ordered another to make sure.
The other thing the bench tests points as possible is U7. When I built it I got U7 mixed up with the other one of its size and had to desolder it and move it. Since its possible it may have damaged that also, I ordered that as well.
Hopefully then I can get it to pass the bench test. If I can't figure it out then it looks like I'll be buying an assembled one and swapping my MSX card to it.
slow_hemi6 wrote:If you build the boards yourself, you have to take the responsibility for the build quality.
Are you saying that with pin24 grounded you are seeing 2.5v on pin2 of u7 and then with 5v on pin24 you are still seeing 2.5v on pin2 of U7? ie No change?
If you are applying 5v to pin 24 and not seeing 4 or more at pin2 of U7 then there is an issue. With the 5v applied what voltages do you measure on each side of R44 and each side of R48?
Check the carefully the soldering of Q22.
To answer you question on the volts I believe it was 21 MV grounded and 25MV powered. Those multimeter pics are the readings. Grounded first then powered
I'm confused and need clarification: with pin 24 either grounded or at 5V you (OP) got nearly 0V at U7 pin2? Slow_hemi, where is there mention of 2.5V on U7-2?
OP, did you do the voltage measurements at each side of R44 and R48? That should be eight separate readings, 2 resistors x 2 leads x ground and 5V to the DB23-24
No hard feelings here, but if I'm not helping just say so; I'll wish you good luck and bow out.
Yeah my bad for not expanding the pics, they are cropped and I could not see the point or scale, but that is why I asked the question to clarify.
21-25mV means that the 5v into pin 24 is possibly not turning off the Q22 transistor. Its a PNP so the base has to go low to conduct and if the base goes high it stops conducting. When the transistor stops conducting pin2 u7 should go high through the circuit Vcc > R48 > R44 > U7 pin 2. A bad U7 could have been shorting that to ground but as you have removed it you could just test the pin2 pad now and see what the voltage is with pin 24 grounded and with 5v.
Maybe too many cooks on this one, I had to go and paint my sons car so that's why I was out for a while.
Find the Manuals up top under Quick links: Manuals.
Cheers Luke
slow_hemi6 wrote:Yeah my bad for not expanding the pics, they are cropped and I could not see the point or scale, but that is why I asked the question to clarify.
21-25mV means that the 5v into pin 24 is possibly not turning off the Q22 transistor. Its a PNP so the base has to go low to conduct and if the base goes high it stops conducting. When the transistor stops conducting pin2 u7 should go high through the circuit Vcc > R48 > R44 > U7 pin 2. A bad U7 could have been shorting that to ground but as you have removed it you could just test the pin2 pad now and see what the voltage is with pin 24 grounded and with 5v.
Maybe too many cooks on this one, I had to go and paint my sons car so that's why I was out for a while.
Painting is fun. Thats what Im in college for. I'll get those readings for you tomorrow as its kinda late now. Im hoping I can save this board. When I get the new Q22, is there a suggested height the black part be from the board? Just curious if the length of the lead from that part to the board would effect it.
High enough to see under it, generally about the same ht as the black body part. It is very difficult to desolder an IC without cooking it or the board. Most guys sacrifice the part by cutting the legs off and then desoldering each leg and gently pulling out, one at a time.
Find the Manuals up top under Quick links: Manuals.
Cheers Luke
slow_hemi6 wrote:Yeah my bad for not expanding the pics, they are cropped and I could not see the point or scale, but that is why I asked the question to clarify.
21-25mV means that the 5v into pin 24 is possibly not turning off the Q22 transistor. Its a PNP so the base has to go low to conduct and if the base goes high it stops conducting. When the transistor stops conducting pin2 u7 should go high through the circuit Vcc > R48 > R44 > U7 pin 2. A bad U7 could have been shorting that to ground but as you have removed it you could just test the pin2 pad now and see what the voltage is with pin 24 grounded and with 5v.
Maybe too many cooks on this one, I had to go and paint my sons car so that's why I was out for a while.
Painting is fun. Thats what Im in college for. I'll get those readings for you tomorrow as its kinda late now. Im hoping I can save this board. When I get the new Q22, is there a suggested height the black part be from the board? Just curious if the length of the lead from that part to the board would effect it.
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I see a lot of boards with these transistors mounted flush. The length of lead makes no difference to the performance of the circuit, but mounting it flush makes it impossible to inspect the soldering on that side - and makes it more difficult to replace if ever needed. On a multi-layer PCB, (in general) the solder needs to flow right through the hole to the other side.
