Did my ECU just shoot the 💩? Update fusible link worked now it won't turn over. New update, SOLVED (1 Viewer)

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Well after our trip to Colorado I noticed the next day when I went to start the truck that it didn't turn over until the second time. Fast forward a few days and after installing the new intake hose and vacuum hoses it did the same thing. Now today after installing the blue clutch fan it did it again. So I drove it around the neighborhood and when I got back home I turned it off then tried to turn it back on. No dice. The check engine light doesn't come on but all the power is still there which leads me to believe it's the ECU (although the lights are quite dim). I've attached a video as well as pictures of the engine bay hoping maybe one of you guys can see something I read somewhere about wires melting which caused this problem with some.



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***Update after fusible links installed:

Well, I got the fusible links installed. Check engine light comes on now but it starts to turn over and then it dies. I've had it hooked up to my wife's tiny 4 banger for 15 minutes and it's still doing this. Lights in the car are on. I'm hoping I can get it going so I can get the battery and alternator checked. The battery looks pretty old but it's weird that all the lights are working and I didn't have any issues with the battery before this. 🤔



Key in the ON position
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***Final update
Make sure to really tighten down the two nuts on the fusible link (inside the black box). Cranked up fine. Still gonna get a new battery though.
 
Last edited:
I really need to work on that valve cover leak 🙄 right after the gear box and now this 😡
 
If you don;t have a CEL at key in the RUN position, then you don;t have the parameters to the ECU met.

First place I would go are the Battery cables.

Second place are Fusible Links. It's possible one leg is burned out, not allowing it to start, but power to accessories (hence (3) legs.)

Use a light between the FL and it's connector to see if you get a light meaning it is grounded out.

Somewhere on here, @jonheld posted a very nice trouble-shoot list for the FL to determine which leg it is just by doing what you can see.
 
If you don;t have a CEL at key in the RUN position, then you don;t have the parameters to the ECU met.

First place I would go are the Battery cables.

Second place are Fusible Links. It's possible one leg is burned out, not allowing it to start, but power to accessories (hence (3) legs.)

Use a light between the FL and it's connector to see if you get a light meaning it is grounded out.

Somewhere on here, @jonheld posted a very nice trouble-shoot list for the FL to determine which leg it is just by doing what you can see.

I can always count on you! I'll look up fusible links. Thanks bud.
 
This is what I'm working with. I'm gonna have to get a volt meter to know 100% so I think I'll just go buy new FLs. Looks like the previous owner went overboard with the lube/grease.

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I'm betting money on that being your issue, seeing the insulation on that blue one......
 
^^^Beat me to it^^^. The protective grease looks original as do the FL's. Definitely replace them, $15-20 at your local Toyota dealer parts professional.

The original nuts in the junction box IME are sometimes difficult to remove by hand, a compact cordless impact wrench makes short work of it. FWIW.

Fusible Link and Junction Box.jpg
 
I'm betting money on that being your issue, seeing the insulation on that blue one......
Let's hope 🤞🏼

^^^Beat me to it^^^. The protective grease looks original as do the FL's. Definitely replace them, $15-20 at your local Toyota dealer parts professional.

The original nuts in the junction box IME are sometimes difficult to remove by hand, a compact cordless impact wrench makes short work of it. FWIW.

View attachment 2389574
Thanks man! Hopefully my local dealer has the part so I can get this fixed ASAP.
 
Somewhere on here, @jonheld posted a very nice trouble-shoot list for the FL to determine which leg it is just by doing what you can see.
 
Well, I got the fusible links installed. Check engine light comes on now but it starts to turn over and then it dies. I've had it hooked up to my wife's tiny 4 banger for 15 minutes and it's still doing this. Lights in the car are on. I'm hoping I can get it going so I can get the battery and alternator checked. The battery looks pretty old but it's weird that all the lights are working and I didn't have any issues with the battery before this. 🤔

 
Might check that pesky EFI relay. You can usually find a less necessary relay and sub it in place of what might be fried as a temp measure. Several of the relays are the same just used in different positions including the EFI one. It's in the panel next to the battery.
 
I'm going to suggest you do some cleaning / mods on your battery terminals.

That specific terminal is designed to have the cable pinched in the center where the ridged groove is. You'll notice there is no paint there.

Where you have your battery and aux terminals on the two bolts under the plate that there is most likely paint on the terminal under your cable lugs. Remove all the paint there in order to optimize your connection. Do this on BOTH terminals.

I chose the mil-spec terminals from Amazon and drilled out the FL end terminal to fit the larger bolt.
 
This past month-On my Fzj80 I had the stuttering RPM, stalling and the engine cranking but not firing. I had replaced all the typical suggestions from ih8mud (EFI relay, fusible link, and even fuel pump) beyond that I replaced ignition coil, distributor and cap and the fuel filter. What finally fixed mine was a brand new ICM.....240k miles of original parts, they do go bad. Hope this helps.
 
I'm going to suggest you do some cleaning / mods on your battery terminals.

That specific terminal is designed to have the cable pinched in the center where the ridged groove is. You'll notice there is no paint there.

Where you have your battery and aux terminals on the two bolts under the plate that there is most likely paint on the terminal under your cable lugs. Remove all the paint there in order to optimize your connection. Do this on BOTH terminals.

I chose the mil-spec terminals from Amazon and drilled out the FL end terminal to fit the larger bolt.
Good eyes and suggestion. I ran into the problem again after the gym. Went and got zinc coated terminals and everything is back to normal.
 

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