Fuel pump open circuit relay question

Shorted wrong terminals on fuel pump open circuit relay blew efi fuse replaced fuse good wont start cranks fine

 

Replace relay under dash too ?

 

I didnt replace the fuel pump open circuit relay since it worked fine when I pulled it. I was trying to get the fuel pump to run to empty the tank but jumped the wrong terminals blew the efi fuse. Replaced the fuse and swapped the relays under the hood.

 

If you jumped the relay wrong. You could have sent 12v directly to the ECM.
Sometimes this cause problems, like ECM problems.

I’d pull that relay and see if you have 2 powers.
If so, make sure the relay is good. Then test the pump for power.
Or be REALLY REALLY CAREFUL and jump the relay again. And HOPE the pump doesn’t run.
If it does, you’re relay isn’t getting commanded to turn on by the ECM. Or the wire from the ECM is bad.

Do you know what pins to jump now? If not, I may be able to dig up a diagram.
@caribe makaira might have diagrams for a 99 Tacoma.

 

Nope...

 

Thanks for looking.

1999 diagrams are hard to find. 2001 are all over. But when it comes to critical wiring, I like to use the year specific.

Thanks again

 

I dont know which pins to jump. Which is why I shorted the dang thing in the first place. Someone suggested it and I was an idiot. It sparked when i touched it to the terminal and i heard a small pop i thought from under the dash/firewall area. The efi fuse had blown, replaced it. It hasn't blown since. I've disconnected the battery neg for more then 15 minutes. Swapped relays and checked all fuses.

 

Here is the engine control wiring diagram (includes fuel pump) for a 1999 5VZ-FE (let me know if I have the wrong engine).

 

Engine 3.4 6cyl

 

I do have the correct engine.

 

Now if I only knew how to read a diagram

 

Thank You Sir!!

 

Do you recall just what pins you jumped that caused your mishap ?

The pin numbers are on the schematic .

 

There are also schematics for the relay as well. It’s usually included with the fuse box diagram in the wiring manual.

Typically, the smaller legs of the relay are control and the larger are feed.

 

Well when holding the plug there is one side flat and the other side is indented because there are two terminals on each side and only one in the middle. So with the indention facing up I touched the middle one (only one hot) to the upper lefthand one I do believe.

 

You are welcome

 

Ok I'm new on here and not real savvy with internet etiquette so if I've missed something or come across as offensive I do apologize. I greatly appreciate any and all input and resources everyone has offered. Thank you. I'm fairly mechanically inclined so I don't know why I cant seem to get familiar with reading electrical diagrams.

 

Ok I looked at the diagram again and I know I jumped the #4 pin to i think it was the #3 pin that caused the problem. Honestly I jumped #4 and started on the right side touching each one listening for the pump to come on. Nothing happened with any of them until I touched #4 and #3 (I think #3) and that's what blew the fuse.

 

So is there anything else it may be since the efi fuse isnt blowing and the relays are all good? ECM?

 

Did you verify operation of the fuel pump as TNshooter mentioned? That would be my first step then start working backwards off the wiring diagram to find out if you're missing power or ground somewhere. Get a test light or volt meter and check for signal from the ECM at the circuit opening relay or directly at the ECM.