More fuel pump relay fun!

Looking at your picture, the main relay is green.

You should have +12 V on one of the terminals in the main relay all the time.
It's sounds like power isn't getting from the INJ fuse to the relay.

Try to clean up the contacts in and under the fusebox. The scorched ones are probably for the main and fuel relays.
 
So basically I have to pull the entire damn harness out of the car.

It dawns on me that this fusebox isn't a power distribution box. Wires bring power in, the power either passes thru a fuse or waits to pass a relay, then leaves to goes to run something like a fuel pump. If it splits, those splits are buried in white plastic and not serviceable. This is even true for the 100 amp main, it comes direct from battery + and goes off into la-la-land in the harness that dives under battery.

From your diagrams, pcb, there should be some indicator where in the harness power comes from, leading to the INJ fuse which is receiving less than 12v, and where it goes in the harness before returning to the fusebox to the fuel pump relay, at which point the juice leakage has reduced it to less than 1v. I have to find the bad spot(s) in the harness.
 
I found this...





Your fuse box is probably OK because it was working.

Focus on the connectors underneath that are kinda scorched.
Try to get continuity from the INJ fuse to the main relay.
 
I just took this picture of my fuse block with the engine off and key removed...



Do you get B+ (11.5 V in your case) between battery negative and the right side terminal in the connector for the INJ fuse ??
 
No continuity between INJ fuse and green main relay. With ignition on, no power to signal side of green main relay.

Fault lies in harness or connectors between INJ fuse and green main relay. Really not looking forward to trying to repair this.

The scorched-looking connectors on the fuse box bottom have no melting, just browned grease, and their metal spare-grabbers look good.

I'm may give up and part the car out over this. I just paid hundreds of dollars for a bonded title and registration, $170 for a new starter, $300 for brand new rear calipers and brackets, $125 for brand new pads and rotors, $400 for new A/C compressor from the rusted out car, and hundreds of hours of my time on stupid crap like mysteriously walking P/S belt and burned out HVAC fan connector, plus swapping catalytic converter and bumper and tailights and door panels from parts car. I'm so mad I could spit. This was supposed to be a reliable daily but it's a piece of crap.
 
I just took this picture of my fuse block with the engine off and key removed...



Do you get B+ (11.5 V in your case) between battery negative and the right side terminal in the connector for the INJ fuse ??

Yes
 
Well...
All I can think of that is cheap and easy is to spray down both sides of the connectors with electrical contact cleaner while plugging them in and out a few times to help scrape a better contact.

Dielectric grease doesn't conduct electricity and the terminals could have a film on them.
 
Just for clarification sake, try a different 30 amp square fuse in the INJ fuse connector.
They're kind of a weird fuse and might not look blown if is.
 
I found some specific info of what wires to test in the harness...







Check for B+ on the "I" terminal W/G wire (white with a green stripe.) of the FB 03 connector (emission harness) that is plugged into the fuse box underneath.

With the plug connected probe into the connector from the back and check for B+.

I'm thinking the ECU won't call for power to the main relay control circuit unless there is power to the main relay.
 
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I'm thinking if you don't have +12 V on the W/G wire then you could splice in a wire to that wire, then to a fuse, then directly to the battery.
That may send the B+ voltage through the W/G wire into the relay.

You could test my hypothesis by just plugging a wire from the battery to a fuse to the W/G wire then test for B+ at the main relay.
You would be essentially be bypassing the bad internal connection and using the backdoor to get power in.
 
If it was me, I'd do this
(although it's Jerry rigged and I'm not addressing the underlying issue,.. I'm bypassing it.)
I was bored and needed some wires with connectors anyway.
I would solder the terminals to the wires if I were using it.



I realized that the power goes from the INJ fuse directly to the main relay and is also sent to a spare pin in the FB 01 socket that is unused.





I removed a connector pin from the connector (you would use your parts car), cut it, spliced into it and plugged it into the L position on the FB 01 connector.
This feeds the power to the ECU... If there's still no continuity between the pin and the ECU then you could splice into the W/G wire in the FB 03 connector as well or instead of.








The R9 pin and wire go to the L position of the FB 01 connector then to a 30 amp fuse, then directly to the battery positive.

You could use short wires and have it quite neat under the fusebox cover.
 
Check for B+ on the "I" terminal W/G wire (white with a green stripe.) of the FB 03 connector (emission harness) that is plugged into the fuse box underneath.

With the plug connected probe into the connector from the back and check for B+.

I'm thinking the ECU won't call for power to the main relay control circuit unless there is power to the main relay.

If you don't have B+ on the white wire with a green stripe then you could feed B+ differently to that wire to send it into the wire going into two pins on the ECU.

That may allow the ECU to turn on the main relay.



You could then pull your INJ fuse and plug the R9 terminal and the wire going to the W/G wire into the INJ socket (with a fuse).
(to provide B+ to the main relay and W/G wire.)


I don't want to see you sell your car.
You may very well be able to get it running with little money and only a few hours of effort.
 
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Holy cow, pcb you are a wizard.

I did yard work, grocery shopping, parenting, and had a stiff drink instead of working on the car yesterday afternoon and evening. It did my attitude a world of good and I'm ready to dive into it again tonight.
 
I went to the car and removed the fuse block, the connectors, and the white wire with a green stripe from the connector just to see how difficult it was.





I think you should start with probing the white/green wire at the back of the connector to check for B+ with everything connected.

I'm almost positive there should be B+ on that wire all the time,.. key in or out.

I've reconsidered trying to feed B+ into the connector backwards to hopefully get power to the main relay because that wire and it's connections are meant for low power not the 30 amps that might need to travel through the main relay.

Taking power for the main relay from the INJ socket makes more sense.

You did say that you got the fuel pump relay going so that should mean the wires and connections from the fuel pump relay to the fuel pump are good.

I don't understand why your replacement fuse block isn't working because the power should go from the INJ fuse to the main relay internally within the fuse block but like you said, the wires come and go into lala land.
 
No voltage reading at green white wire.

Wiring harness looks intact externally. It looks insane to pull out even on my engine-less parts car.
 
If you remove the white/green wire from the connector, you can put it back in if the bypass doesn't work.
You could feed B+ to the metal clip, as well as B+ to to the R9 terminal of the main relay, all with temporary connections and see if it works.

Replacing the harness sounds like a real chore. The wires get old, stiff and brittle and can break internally without being visible.
 
A really easy test would be to just simply feed B+ straight from the battery to the backside of the connector with a length of wire and stuff it into the white/green wire terminal to see if the main relay kicks in.
 
Swapped original fusebox back in, retook all readings:

Zero at green white wire again. Note that I tested all the terminals in the long white connector, some had stray voltage and one had 3.15 volts. Then I plugged it back in.

INJ fuse terminals getting clean 12v.
(INJ fuse tests perfect continuity)
Zero at green main relay signal side.
Zero at fuel pump relay signal side, of course.

I then put the parts car fusebox back in because it's got less scorching on fuel pump relay terminal, and shut down operations for the night.

If you remove the white/green wire from the connector, you can put it back in if the bypass doesn't work.
You could feed B+ to the metal clip, as well as B+ to to the R9 terminal of the main relay, all with temporary connections and see if it works.
I don't have a sufficient array of spark-wizard clippy wires to perform this magic trick. I will set about acquiring them.

Replacing the harness sounds like a real chore. The wires get old, stiff and brittle and can break internally without being visible.
Agreed. But that's probably where the broken wire is that fuch'ed this car.

Even if temporary bypass connections send power to fuel pump and starts the car, I can't drive it like that - the repairs need to be made. I'm going to have to slit open the parts car's harnesse and find where the wires go from the INJ fuse on that chart and from the green white wire. Then dig into Blue Lemon's harness. F.M.L.
 
I removed my fuse block from my parts car.



I have continuity between the left side of the INJ fuse socket and my R9 terminal in my main relay.

That connection is internal, inside the fuse block.

Check to see if you have continuity.
 
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