'86 MJ 2.5L ECM....good?

[eaglescout526]

Pin 85 to T6

86 goes to the ignition switch.

[SoCalManche]

6 minutes ago, eaglescout526 said:

Then theres the pump will not operate with starter engaged.

Connect positive battery voltage to the pump contact on the starter motor relay

I already have a 4AWG that is connected to the start solenoid and Batt Pos post. Am I to remove the fusible link from the starter solenoid and connect directly to Batt Pos post?

 

8 minutes ago, eaglescout526 said:

If pump does not operate, repair wire harness between the starter motor relay and the pump side of the ballast resistor. Not sure if that is for Renault models or both.

Then it says to check the one second operation.

So yeah, I don't have a ballast resistor.

[eaglescout526]

All it says is to connect positive battery to the pump contact on the starter motor relay. Doesn't say how. So my guess is it is a spade connecter and not one of the fusible links that is held down by the nut on the relay.

[SoCalManche]

4 minutes ago, eaglescout526 said:

Pin 85 to T6

86 goes to the ignition switch.

I retested to verify. Continuity beep is loud and proud for Pin 85 & T6.

[eaglescout526]

Ok so no trouble with that circuit. So the relay should energize, still not sure why it won't do the prime sequence.

[SoCalManche]

8 minutes ago, eaglescout526 said:

All it says is to connect positive battery to the pump contact on the starter motor relay. Doesn't say how. So my guess is it is a spade connecter and not one of the fusible links that is held down by the nut on the relay.

So this is my view. Not sure what it's asking because the harness to the fuel pump relay is way the hell over there compared to the starter solenoid. There's that 4AWG connection I was talking about too.

[eaglescout526]

No its not saying to have a wire go to the FP relay, but on the starter relay is also a terminal that triggers the fuel pump to run during start up. I do not know which terminal that is.

[SoCalManche]

1 minute ago, eaglescout526 said:

No its not saying to have a wire go to the FP relay, but on the starter relay is also a terminal that triggers the fuel pump to run during start up. I do not know which terminal that is.

Are you referring to one of those three plugs on the starter solenoid?

[eaglescout526]

Yes I am.

[SoCalManche]

3 minutes ago, eaglescout526 said:

Yes I am.

Will I hurt anything if I use a jumper on all of them to test it out?

 

 

Edit: Also, should those connectors stay connected while testing?

[eaglescout526]

Theres nothing on the starter relay to test....I wonder why the book would say to look there. I just looked at the electrical schematics for the relay and fusible links and only saw the one fusible link for the ECU, FP relay and B+ relay.

 

So theres nothing on the starter relay to give power to.  

[SoCalManche]

2 minutes ago, eaglescout526 said:

Theres nothing on the starter relay to test....I wonder why the book would say to look there. I just looked at the electrical schematics for the relay and fusible links and only saw the one fusible link for the ECU, FP relay and B+ relay.

 

So theres nothing on the starter relay to give power to.  

What about the B+ Latch Relay? Can we test that? I've seen other posts about that causing No-Start issues.

[eaglescout526]

Check the B+ relay. Check the wire harness and connectors, repair or replace as necessary. But the possible cause of the B+ would be no battery voltage applied to the injector(12V from one pin to the chassis ground).

 

That's what the book says, but nothing on how to test it.

[SoCalManche]

1 minute ago, eaglescout526 said:

Check the B+ relay. Check the wire harness and connectors, repair or replace as necessary. But the possible cause of the B+ would be no battery voltage applied to the injector(12V from one pin to the chassis ground).

 

That's what the book says, but nothing on how to test it.

Dammit, lol.

[eaglescout526]

Yeah the book shows you how to locate it and remove it. I am not sure what would happen if we jumped the 30 to the 87 though. 

[SoCalManche]

7 minutes ago, eaglescout526 said:

Yeah the book shows you how to locate it and remove it. I am not sure what would happen if we jumped the 30 to the 87 though. 

All If found was that Pin 30 on FPR is supplied power by B+ Latch Relay. Not sure how, though.

[eaglescout526]

I meant on the B+ relay, pin 30 on both relays should go right into a fusible link. This is tons of fun!

[SoCalManche]

11 minutes ago, eaglescout526 said:

I meant on the B+ relay, pin 30 on both relays should go right into a fusible link. This is tons of fun!

For sure. I've got a headache from the uncertainty of all this. Ha, guess I'll sift through more split loom tomorrow since I'm not sure what else to do.

[eaglescout526]

SatiricalHen is going to a salvage yard tomorrow for some cruise control stuff, he says he knows where an 86 2.5L is, so he said he will snag the ECU from it. Id pretty much go through the wiring before you drop in a new ECU just to prevent the same issue from happening to a new to you or reman ECU. I mean I still think it is something in the fuel pump circuit but we are running low of things to test.

 

You should pour some fuel down the TB tomorrow and see if the ISA will function after shut down.

[SoCalManche]

4 minutes ago, eaglescout526 said:

SatiricalHen is going to a salvage yard tomorrow for some cruise control stuff, he says he knows where an 86 2.5L is, so he said he will snag the ECU from it. Id pretty much go through the wiring before you drop in a new ECU just to prevent the same issue from happening to a new to you or reman ECU. I mean I still think it is something in the fuel pump circuit but we are running low of things to test.

 

You should pour some fuel down the TB tomorrow and see if the ISA will function after shut down.

When I wake up, I'll do that test and send you a video. Tell SatiricalHen to PM me and I'll chat with him.

[eaglescout526]

Sounds good and will do!

[Ωhm]

@eaglescout526 Nice job on proving out CTS and WOT switches. I think my testing flaw came with leaving the ECU connected to the harness. Lesson learned.

[SoCalManche]

1 hour ago, Ωhm said:

@eaglescout526 Nice job on proving out CTS and WOT switches. I think my testing flaw came with leaving the ECU connected to the harness. Lesson learned.

Glad we're all learning here! I wouldn't mind this lesson ending sooner than later, for all of our mental sakes.

 

Here is a video of the MJ firing via fuel down TBI again, with freshly cleaned ISA. I don't necessarily know what you're looking for @eaglescout526 but it doesn't look like anything is moving;

 

https://drive.google.com/open?id=14ZzcfRGiSK9ddeWep9ZBAZk8EQwiajYv

[eaglescout526]

2 hours ago, Ωhm said:

@eaglescout526 Nice job on proving out CTS and WOT switches. I think my testing flaw came with leaving the ECU connected to the harness. Lesson learned.

Thank ya!

 

Shame, ISA motor might be chunked, but we ruled out a completely closed throttle being a problem. 

 

But we still don't have the fuel pump running when cranking with the relay. 

[SoCalManche]

2 minutes ago, eaglescout526 said:

Thank ya!

 

Shame, ISA motor might be chunked, but we ruled out a completely closed throttle being a problem. 

 

But we still don't have the fuel pump running when cranking with the relay. 

Is the ISA motor toast, or is it the ECU playing the role of electrical gremlin, causing it to not act right? Or maybe I'm wrong since it seems to be getting the proper voltage on the harness?