96 fzj80 crank no start

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I've been neglecting my 80 because I've got other projects and now it wont start. When I turn the car on I don't have a CEL or codes. I replaced the pump but I still didn't hear the pump start up when I turned the car on. I've been able to spray starter fluid into the throttle body and get the engine to fire up. I tried jumping the fuel pump relay at the #3 connector to +12v from the battery but still didn't hear the pump kick on. There is 12v at the B+ terminal on the diagnostic port. There is also 12v at the brass screw on the fusebox where the EFI relay is. The vehicle also has fresh gas in it.

I normally don't throw parts at a problem but I did in this case.

New Parts:
Fuel Pump
Fuel Pump Relay
EFI Relay
Open Circuit Relay
Fusible Links

Anyone have any ideas on what I should be looking for?
 
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What year?
What engine?
Sorry, didn't read the heading.
If you're not getting a CEL with the key in the ON/RUN position, the ECU is not in a ready state and this engine will not run.
What dash lights are illuminated with the key in the ON/RUN position?
 
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So, when you turn the key to RUN, is the CEL illuminated?

If not, then there is something not allowing the ECU to be in a ready state. Assuming, of course, that the bulb in the CEL is good.

Check the fusible links and ALL of the fuses under hood as well as inside the cabin. Make sure to check them with a meter, as some can be blown and not be visually obvious.

The fuel pump will not run unless the engine sees a signal from the crank sensor that it is actually rotating. (Unless you install a jumper to force it to run, then it should run. If not, you have a bad pump.
 
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Joined
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What year?
What engine?
Sorry, didn't read the heading.
If you're not getting a CEL with the key in the ON/RUN position, the ECU is not in a ready state and this engine will not run.
What dash lights are illuminated with the key in the ON/RUN position?
Took a picture of the lights. I noticed the oil light is also not showing.

lcDash.jpg
 
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So, when you turn the key to RUN, is the CEL illuminated?

If not, then there is something not allowing the ECU to be in a ready state. Assuming, of course, that the bulb in the CEL is good.

Check the fusible links and ALL of the fuses under hood as well as inside the cabin. Make sure to check them with a meter, as some can be blown and not be visually obvious.

The fuel pump will not run unless the engine sees a signal from the crank sensor that it is actually rotating. (Unless you install a jumper to force it to run, then it should run. If not, you have a bad pump.
I checked all the fuses for continuity in both locations and everything was good.

I did try to jump from the battery to #3 on the FPR and got nothing but the fuel pump is brand new. Am I going about this the wrong way or is the fuel pump actually bad?
 
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I replaced the pump but I still didn't hear the pump start up when I turned the car on.

Assuming you mean the fuel pump, it isn't activated when you turn the ignition to the on position. The fuel pump is controlled by the ECU. I think I've read that it isn't activated until some oil pressure threshold is reached, but I haven't found an explanation in the factory service manual.
 
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@rozzay what were the symptoms before you replaced all the parts?

Same problem before and after the parts cannon??
 
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@rozzay what were the symptoms before you replaced all the parts?

Same problem before and after the parts cannon??
Just crank no start. I tested spark plugs and they were fine. Started it up with starter fluid. Made sure there was gas in there. I tried jumping the FPR and the FP didn't do anything so I replaced the FP. Then I threw everything but a fuel filter at this problem lol.

I've seen other threads talk about jumping the B+ terminal with the Fp on the diag port but my Fp doesn't have a terminal in there.
 
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As previously stated, without the CEL illuminated with the key in the ON position, this engine will not run. It is telling you that the ECU is not in a ready state. The ECU runs the show from the fuel pump to the injectors to spark. There's no bypassing this. You need to determine why the CEL is not lit.
If the fuses and fusible links (all 3) are known good, then look for connectors EB1 and EA1 in the engine bay. EFI circuits pass through those 2.

1658455685273.png


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1658455791471.png
 
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As previously stated, without the CEL illuminated with the key in the ON position, this engine will not run. It is telling you that the ECU is not in a ready state. The ECU runs the show from the fuel pump to the injectors to spark. There's no bypassing this. You need to determine why the CEL is not lit.
If the fuses and fusible links (all 3) are known good, then look for connectors EB1 and EA1 in the engine bay. EFI circuits pass through those 2.

View attachment 3065521

View attachment 3065524

View attachment 3065527
Thanks @jonheld , I'll look into checking these out today.
 
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Joined
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As previously stated, without the CEL illuminated with the key in the ON position, this engine will not run. It is telling you that the ECU is not in a ready state. The ECU runs the show from the fuel pump to the injectors to spark. There's no bypassing this. You need to determine why the CEL is not lit.
If the fuses and fusible links (all 3) are known good, then look for connectors EB1 and EA1 in the engine bay. EFI circuits pass through those 2.

View attachment 3065521

View attachment 3065524

View attachment 3065527
Both connectors look fine. I tested EB1 and it was getting 12v. I went through and tested the terminals on EA1 and I think all the correct terminals had 12v. Although #4 did have a little bit below 12v. I do have a red light on above the battery voltage on the dash.

I think I read in one of the FAQ Troubleshooting threads that a red charging light could mean that the AM2 fusible link is bad. Is that true?
 
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Both connectors look fine. I tested EB1 and it was getting 12v. I went through and tested the terminals on EA1 and I think all the correct terminals had 12v. Although #4 did have a little bit below 12v. I do have a red light on above the battery voltage on the dash.

I think I read in one of the FAQ Troubleshooting threads that a red charging light could mean that the AM2 fusible link is bad. Is that true?
No. The charge light is lit because the engine is not running. If the charge light was NOT lit with the key in the ON position, then it could be AM2.
Please don't loose your focus here. Your only concern is the lack of the CEL. Nothing else matters.
 
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I think I read in one of the FAQ Troubleshooting threads that a red charging light could mean that the AM2 fusible link is bad. Is that true?
You also said that the fusible links were replaced. Did you replace the set of 3 fusible links off the positive battery terminal? 2 go to the black junction box and 1 to a grey connector.

 
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You also said that the fusible links were replaced. Did you replace the set of 3 fusible links off the positive battery terminal? 2 go to the black junction box and 1 to a grey connector.

Yeah I did replace it. I had to cut the eyelet off the end of the fusible link and strip the wires then crimp down on them with whatever this thing is that the PO had installed. I'll drop a picture. I remember having a hard time with the pink wire because its such a small gauge wire that it kept slipping out. I'm going to take a wild guess and say that powers the ECU in someway?

80SeriesFusible1.jpg
 

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