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Discussion Starter #1
I just picked up this '90 Bronco, and when it sits for a day, the battery is flat dead. When I put a charged battery in and connect the cables, the Fuel Pump relay clicks, and I can hear the fuel pump prime and shut off. Is this supposed to happen??? I thought the fuel pump was supposed to prime only after the ignition key was turned to the 'On' position?

I haven't had an opportunity to get into it yet, but figured I would throw this thread out there to steer me in the right direction, if this is a common problem with these? Thanks for your time and help.

Joe
 

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Sounds like your eec is getting power all the time, Probably an ignition switch. I would doubt there is anything wrong with the fuel pump, relay, and EEC
 

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Discussion Starter #3
^^^ That was my first suspicion; Odd thing is that no other accessories work or can be turned on until rolled over to 'On'? You would think if the switch were bad, that it would just relay the current to everything as well as the Fuel Pump Relay?
 

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Discussion Starter #4
-Battery is 12.5V at the posts: Good.

-With key off no accessories work, like radio, wipers, windows: Good.

-FP Relay, red wire's post to other small out has continuity: Good.

-FP relay Plug; Yellow wire is at 12.5V with key off, I believe supposed to be constant power supply: Good.

-FP relay Plug; Red wire is at 12.46V with key off, I believe supposed to be dead until tripped by key: Bad


So, I guess my questions now are: A) are my assertions above correct? And B) if so, does that mean my ignition switch is faulty, or does that mean the EEC Relay is faulty and forwarding on the current to the FP Relay?

Thanks for any help.

Joe :kiss
 

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Discussion Starter #5
I think I found my own problem ... the EEC Relay:

-Yellow wire going into it is hooked up to constant Battery power: Good.

-Red/Lt Green wire going into it from the ignition switch is dead: Good, no power with key off.

-Red/Lt Green wire from ignition switch gets power when turned to 'On': Good.

-Red wire out of EEC Relay goes over to the Fuel Pump Relay Red in, once the ignition key is turned to 'On': BAD, power is being transmitted with key off!

When I pulled the EEC Relay out and checked continuity across the pins, it is dead from Key into Black ground out; Without power going into the Yellow spade, it has no continuity over to the Red, but obviously when hooked up to Battery current it is Relaying that power over to the Fuel Pump relay, but shouldn't be, since the ignition key wire is dead.

Hopefully that is it, and the battery draining problem is not multiple things? :whiteflag
 
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