EFI 15 amp fuse blowing (2 Viewers)

[Anvil]

Do you have the Toyota EWD? This is all laid out for you.
The EFI relay gets +12 on pin 2 from the 15 amp EFI fuse. The 15 amp EFI fuse is fed from the MAIN fusible link.
However if the MAIN fusible link was faulty, you'd have no headlights, no tail lights, no brake lights, various others, and no CEL with the key in the ON position.
The combination of the FSM and EWD is invaluable.

View attachment 3578523

Do you have the Toyota EWD? This is all laid out for you.
The EFI relay gets +12 on pin 2 from the 15 amp EFI fuse. The 15 amp EFI fuse is fed from the MAIN fusible link.
However if the MAIN fusible link was faulty, you'd have no headlights, no tail lights, no brake lights, various others, and no CEL with the key in the ON position.
The combination of the FSM and EWD is invaluable.

View attachment 3578523

Thank you for posting this! I'll be working again on my girlfriends 95 tomorrow. I downloaded the 96 EWD and have been studying the wiring diagrams. I've learned a lot in the past week. Though one part still has me stumped... The vehicle will drive fine for 10 miles or so before blowing the 15 amp efi fuse. Once the fuse is blown, the 80 will only travel 1/4 - 1/2 mile before blowing again.

Jonheld, Thank you for your input. I appreciate your time!!!

 

[jonheld]

Thank you for posting this! I'll be working again on my girlfriends 95 tomorrow. I downloaded the 96 EWD and have been studying the wiring diagrams. I've learned a lot in the past week. Though one part still has me stumped... The vehicle will drive fine for 10 miles or so before blowing the 15 amp efi fuse. Once the fuse is blown, the 80 will only travel 1/4 - 1/2 mile before blowing again.

Jonheld, Thank you for your input. I appreciate your time!!!

Go back and read post #16 in this thread. Something is shorting to ground, which is popping the EFI fuse.
Use a meter set to continuity (with a beep tone if possible). 1 lead in the load side of the EFI fuse terminal, the other on a good ground or negative battery terminal, and start moving wiring harnesses around.
When you get a beep or read continuity, you have found the fault.

 

[Anvil]

Go back and read post #16 in this thread. Something is shorting to ground, which is popping the EFI fuse.
Use a meter set to continuity (with a beep tone if possible). 1 lead in the load side of the EFI fuse terminal, the other on a good ground or negative battery terminal, and start moving wiring harnesses around.
When you get a beep or read continuity, you have found the fault.

THANK YOU!

 

[jonheld]

THANK YOU!

The load side of the EFI fuse is the terminal that is NOT getting constant +12.

 

[Anvil]

Problem solved!

The plastic clips on the frame, that holds the wiring harness above the front driveshaft, were broken and allowing the harness to rub on the driveshaft. Three wires, red/yellow, orange. and blue were exposed. Some waterproof connectors, new wire loom, and zip ties fixed the problem.

Thank you to everyone who chimed in! I learned a lot the past two weeks. Your help is much appreciated!!

 

[ZackR]

Problem solved!

The plastic clips on the frame, that holds the wiring harness above the front driveshaft, were broken and allowing the harness to rub on the driveshaft. Three wires, red/yellow, orange. and blue were exposed. Some waterproof connectors, new wire loom, and zip ties fixed the problem.

Thank you to everyone who chimed in! I learned a lot the past two weeks. Your help is much appreciated!!

View attachment 3582286

View attachment 3582287

02 sensor wiring, called it in post 9. Your welcome

 

[jonheld]

02 sensor wiring, called it in post 9. Your welcome

Called it in post #7.

 

[Two 3FEs]

Do you have the Toyota EWD? This is all laid out for you.
The EFI relay gets +12 on pin 2 from the 15 amp EFI fuse. The 15 amp EFI fuse is fed from the MAIN fusible link.
However if the MAIN fusible link was faulty, you'd have no headlights, no tail lights, no brake lights, various others, and no CEL with the key in the ON position.
The combination of the FSM and EWD is invaluable.

View attachment 3578523

AS it turned out, I did have +12 to the EFI ports on the ECU. So I thought the ECU itself was bad. i sent it to SIA Electronics (eBay). They checked it out as perfect for $90 free shipping back. Due in this afternoon.
What I completely fail to understand is why the EFI still wasn't running. I checked fuel pressure on the cold start line and it sprayed fuel all over the hood. And remember that this truck was doing 75 on the way home night before it died.
I really need help with this. Driving me crazy and there is no shop around here that will work on it.

 

[jonheld]

AS it turned out, I did have +12 to the EFI ports on the ECU. So I thought the ECU itself was bad. i sent it to SIA Electronics (eBay). They checked it out as perfect for $90 free shipping back. Due in this afternoon.
What I completely fail to understand is why the EFI still wasn't running. I checked fuel pressure on the cold start line and it sprayed fuel all over the hood. And remember that this truck was doing 75 on the way home night before it died.
I really need help with this. Driving me crazy and there is no shop around here that will work on it.

You're posting in someone else's thread with a different problem.
Start your own thread with details on the issue. If you already have a thread, please post in it and point to it so others can help you.