3p141592654;1930541 said:
THIS IS PERFECT!!! thats exactly what I needed to see. Thank you very much.
87 7MGTE No Spark; In desperate need of help in NORFOLK
- Thread starter Mueller87
- Start date
THIS IS PERFECT!!! thats exactly what I needed to see. Thank you very much.
just took these
here's my question though... if the two cps's I have are indeed from a 1987 supra turbo, same as the one in the picture 3p14 posted, then why is it that the wires are a different color from the harness? I mean it seems pretty clear that the white wires I have are grounds. and then it only stands to reason that the colored wires are the important ones. I can get a ground anywhere but If I have red green and yellow vs red blue and yellow How do I know which one goes where? see the bunch of wires coming out of the CPS is CUT. the wires for the CPS coming from the harness are CUT. they colors do not match...
by the way, I have no intention of troubleshooting the EFI system before I have spark... unless for some odd reason the EFI system has to be 100% for the spark to occur. Then I'd start there. But to me and in the case of anything I've done before they were independent on one another.
here's my question though... if the two cps's I have are indeed from a 1987 supra turbo, same as the one in the picture 3p14 posted, then why is it that the wires are a different color from the harness? I mean it seems pretty clear that the white wires I have are grounds. and then it only stands to reason that the colored wires are the important ones. I can get a ground anywhere but If I have red green and yellow vs red blue and yellow How do I know which one goes where? see the bunch of wires coming out of the CPS is CUT. the wires for the CPS coming from the harness are CUT. they colors do not match...
by the way, I have no intention of troubleshooting the EFI system before I have spark... unless for some odd reason the EFI system has to be 100% for the spark to occur. Then I'd start there. But to me and in the case of anything I've done before they were independent on one another.
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Well, the CPS also drives injection. Not that any of what you're doing at the moment is going to matter if there's no +B. You're dead in the water without it.
Ahhh I see. That makes sense now that I think about it. With this kind of setup it doesn't make sense not to do it that way.
What you're doing still needs to be fixed but without +B (which is ECU main power) the CPS signals can't be processed. Bottom line is at some point you'll have to get the MIL working. You're going to need a meter, know how to use it, and be able to read the schematics. If you can't do that it's going to be a struggle. Refer to 3p's excellent advice in post 20 as a start.
so the fuses are good, and I'm moving onto check the 'b+' lines. Im hoping that as much as everyone has helped so far someone won't mind telling me where and how I check this. I know I can do it with my test light, and I have to assume its inside the tiny diagnostic port on the inner drivers side fender. I already tested them all with the ignition on and I got voltage at one spot, So if I'm in the right spot I guess I need to see the identification of these ports. I've seen it before but now I can't find it...
Edit: I found B+ and this didn't have 12v. I will double check but I only had voltage at TS.
Edit: I found B+ and this didn't have 12v. I will double check but I only had voltage at TS.
With B+ confirmed DEAD, that puts me dead in the water. If anyone could tell me what this B+ terminal represents, that would be awesome. In the morning I will pick up a multimeter and start getting serious about this.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=47
So I'm assuming that and the following two pages are undecipherable?
The ignition switch sends 12 volts to terminal IGSW on the ECU. Since the ECU always has battery power on terminal BATT, 12 volts on IGSW causes it to "wake up" and output 12 volts on terminal M-REL. That turns on the Main Relay in the underhood fuse box.
The relay closes and send 12 volts (this 12 volts is +B) to terminals +B and +B1 and to the diagnostic connector. Once the ECU is powered it outputs a ground on terminal W. This ground illuminates the MIL. Assuming the lamp is good this is why the MIL can be used as a indication +B is present.
When the ignition switch is turned off and the 12 volts on IGSW goes away the ECU takes a few seconds to home (fully open) the idle speed control valve and afterwards shuts the Main Relay off, killing power to itself. It then "waits" for IGSW again.
So I'm assuming that and the following two pages are undecipherable?
The ignition switch sends 12 volts to terminal IGSW on the ECU. Since the ECU always has battery power on terminal BATT, 12 volts on IGSW causes it to "wake up" and output 12 volts on terminal M-REL. That turns on the Main Relay in the underhood fuse box.
The relay closes and send 12 volts (this 12 volts is +B) to terminals +B and +B1 and to the diagnostic connector. Once the ECU is powered it outputs a ground on terminal W. This ground illuminates the MIL. Assuming the lamp is good this is why the MIL can be used as a indication +B is present.
When the ignition switch is turned off and the 12 volts on IGSW goes away the ECU takes a few seconds to home (fully open) the idle speed control valve and afterwards shuts the Main Relay off, killing power to itself. It then "waits" for IGSW again.
http://www.turboninjas.com/mk3supra/1987/04-EFISystem.pdf
Page 33-41 should be a little easier to understand if you can't follow wiring diagrams
Page 33-41 should be a little easier to understand if you can't follow wiring diagrams
jetjock;1930574 said:
Well said, not sure if it could be put into any easier to understand terms.
I know when we had a situation like this on my friends car, his kick panel fuse box had fuses in there that weren't touching both sides of the terminals. We had double and triple checked them but didn't think to make sure they were all touching, so after some frustrated wiggling of everything, the CEL came on with the key switch on. We just ever so slightly bent the tabs on the fuses to make sure contact was made. He had power to B+ though.
To the above comment about checking fuses, I always give each fuse a little push to make sure they are in all the way. Than have my multi meter negative probe to a known good ground and use the positive probe to check voltage on each side of the fuse one at a time instead of just check continuity, which will only tell you if the fuse is completely blown where this way will verify the signal is actually running through the fuse like it should