injector bank #2 and fuel pump ground

[DaveEFI]

If you're sure it loaded OK, sounds like a processor fault.

[christiondavid]

yes what I do see is that d5 has 11.6 volts on banded side and d7 has 5.9 volts on banded side like not enough porwer getting to the injector bank #2

[christiondavid]

ok after some more testing with my multimeter on the injector bank #2 found the problem and fixed it it was (d20) so that's fixed now I have to check why the fuel pump wont work daughter card out fuel pump light off with daughter card back in with no rpm light is on with rpm light turns off crazy things that happen going to see what I can do with that problem

[christiondavid]

So let me ask if on the stim with everything turned to off and the fuel pump light is on and then with rpm the light turns off what would cause it to work in reverse of how it should really work like turn on for a second and turn off then with rpm stay lit but nope not in this case any thoughts and yes i did the firmware 3 times stayed the same.

[DaveEFI]

You've said the pump LED is off with the daughter card removed. With it still removed, run a jump wire from +5v to pin 33 of the socket. (If a V3 board, the proto area is a good place to find 5V) The LED should now light. If this checks out OK, the fault must be in the daughter card.

[christiondavid]

Thank you dave i will give that a go when i get out of work and thanks a millon for your help

[christiondavid]

ok I just did the test from 5v to pin 33 no light what should I be looking for now? again ty very much.

[christiondavid]

should I have any type of power on r40 with stim any side because I don't see any power on r40 with or with out rpm

[DaveEFI]

ok I just did the test from 5v to pin 33 no light what should I be looking for now? again ty very much.

Just a thought before going on. You are certain it was pin 33? You found the pin marked 1 on the socket and counted round? (the socket is upside down on the PCB)

If so, that's actually good news as it means a fault in the pump driver circuit, which is going to be cheaper to fix than the daughter card. But doesn't explain the LED being constantly on with the daughter card plugged in.

Just to re-cap. You built this board yourself, and this driver circuit has never worked properly?

If so, first thing to do is examine it very carefully to make sure all components are correctly fitted. And no solder bridges at the transistors. Have you mounted the transistors tight to the PCB so you can't see the solder on that side of the board?

[christiondavid]

ok I just did the test from 5v to pin 33 no light what should I be looking for now? again ty very much.

Just a thought before going on. You are certain it was pin 33? You found the pin marked 1 on the socket and counted round? (the socket is upside down on the PCB)

If so, that's actually good news as it means a fault in the pump driver circuit, which is going to be cheaper to fix than the daughter card. But doesn't explain the LED being constantly on with the daughter card plugged in.

Just to re-cap. You built this board yourself, and this driver circuit has never worked properly?

If so, first thing to do is examine it very carefully to make sure all components are correctly fitted. And no solder bridges at the transistors. Have you mounted the transistors tight to the PCB so you can't see the solder on that side of the board?

I did the test to pin 33 to 5v 3 times just to be safe with the ms2 db9 to my left pin 21 qnd 22 on top to the left that's where I did the test for the injector lights but yes the pump worked ok all I did was install the ms2 into the car wired up everything did the realy for the fuel pump just like it calls for but and I found that issue, on the stim everything seam to work ok until wired in car then found that injector bank #2 was not firing found and fixed that problem then for what ever reason the pump would not come on so brought the msn inside when I tested it with the stim again noticed that the light for the fuel pump would stay on with no rpm but would go out with rpm tested like you said pin 33 with daughter card out to 5v proto aera no light and this is where I stand so far with the fuel pump drive.

[DaveEFI]

The pump driver circuit is pretty simple with only 5 components, apart from the various PCB tracks. The most likely thing is Q2 has failed, if it did once work correctly.

With that link to pin 33 in place and it powered up via the stim, you could measure the volts at pins 1,2&3 on both transistors, (Q19&2) and post here.

Assuming the FIDL driver is still standard, that is exactly the same circuit, so with them both in the same state, on or off, you could compare voltages, same as with the two injector drivers.

[christiondavid]

ok took some readings with multimeter db9 to my left db37 to my right ms2 upside down, letters upside down, daughter card in everything set to off calling pin number one from bottom up, calling bottom heat sink aera (q19 pin1 0volts pin2 0volts pin pin3 1.6 volts) this is with everything set to off pluged into stim power on, ok now with rpm Q19 pin1 0volts and second pin2 0volts pin3 4.8 volts, now q2 with out power first pin no volts second pin 1.6volts and third pin 2.7 volts, now with rpm first pin no volts second pin 4.8 volts and third pin 4.8, this is with db9 to my left db37 to my right heat sink I am calling bottom working my way up, thanks again for your help.

[DaveEFI]

If you look at the circuit, Q2 should act like a switch when turned on. So with that 5v to Pin33, should read about 0v on its output, pin3. Actually something like 0.6v. That then supplies the ground to the pump relay. So it looks very much like Q2 has failed.

[christiondavid]

If you look at the circuit, Q2 should act like a switch when turned on. So with that 5v to Pin33, should read about 0v on its output, pin3. Actually something like 0.6v. That then supplies the ground to the pump relay. So it looks very much like Q2 has failed.

Thanks Dave I will change Q2 out and I will let you know how that gos again thank for all the help.

[DaveEFI]

I still can''t guess how the pump worked on the car if the relay driver circuit doesn't work, though.

[christiondavid]

I still can''t guess how the pump worked on the car if the relay driver circuit doesn't work, though.

Worked on the stim in a normal way but when wired into car I had those problems, but I do have a question I don't have a Q2 can I replace Q2 with a Q6 it is a non?

[christiondavid]

I still can''t guess how the pump worked on the car if the relay driver circuit doesn't work, though.

Worked on the stim in a normal way but when wired into car I had those problems, but I do have a question I don't have a Q2 can I replace Q2 with a Q6 it is a non?

Sorry ment to say npn

[DaveEFI]

No. You need a transistor capable of handling the current the relay coil takes. Otherwise MS would have used the same transistor for both jobs. There are lots of transistors that would work OK, but the 2N2222 is the most obvious substitute for a ZTX450, although it handles slightly less current than the ZTX 450, but is still OK for a relay. In the UK, you can buy 100 2N2222 form Ebay for about a couple of dollars with free postage.

[christiondavid]

No. You need a transistor capable of handling the current the relay coil takes. Otherwise MS would have used the same transistor for both jobs. There are lots of transistors that would work OK, but the 2N2222 is the most obvious substitute for a ZTX450, although it handles slightly less current than the ZTX 450, but is still OK for a relay. In the UK, you can buy 100 2N2222 form Ebay for about a couple of dollars with free postage.

I have a few pn2222a is that the same could I use that?

[christiondavid]

No. You need a transistor capable of handling the current the relay coil takes. Otherwise MS would have used the same transistor for both jobs. There are lots of transistors that would work OK, but the 2N2222 is the most obvious substitute for a ZTX450, although it handles slightly less current than the ZTX 450, but is still OK for a relay. In the UK, you can buy 100 2N2222 form Ebay for about a couple of dollars with free postage.

I have a few pn2222a is that the same could I use that?

Never mind I found a bag full of ztx450 in my stash of part I am going to replace it and I will let you know if that fixed my problem sorry Dave for all the questions but thank you big time for your help