I own an 87 ford bronco 2 4wd as my river toy. I took it down to the river last night and it quit about 15 miles in. Was stumped couldnt figure out what was wrong with it so i had to tow it out of the river and home. It ran perfectly fine and then just quit. I noticed that the fuel pump no longer primed when i turned my key so i went under the hood to see if the relay clicked. No click. I thought ah ha! alas! Replaced fuel pump relay and still nothing. If anyone could give any suggestions to what else i should try please do. I also bypassed the inertia switch underneath the hood because the inertia switch was burnt out and it would just burn through another in the river.

 

There should be a small ground wire from the negative post on the battery that connects to the core support. At that connection there should be several other wires. One of them is the ground wire for the relays. Check them over real good and make sure they have good connections. I have also seen a loose ground strap from the back of the head to firewall cause the same problem.

 

The wire that connects from the neg post on the battery is screwed in right by the radiator. I cleaned up that connection and screwed back in. there was only one other wire connecting from it and i will find out where it leads. As to the back of the heads to the firewall i have no idea what your talking about or what to even look for. if you could supply me more information on that it would be greatly appreciated! thanks

 

I found the ground strap and it is connected still it does have alot of junk on the backside of the head so im goiung to disconnect both ends and clean them up then reconnect in the morning the two wires leading from the grill area by the radiator are going to the headlights. and also i checkd the voltage on the relay plug not the actual relay and all of them had voltage except one that was without the key turned. I was wondering if they should all have voltage?

 

I took the ground strap of and tested it. ground strap fine. cleaned it up put it back on and nothing. there is no power coming from the relay im going to test all of the sockets in the plug. how many sockets should i have?

 

I noticed in your original post you said (the inertia switch under the hood) In all my bronco ll's the inertia switch was under the top of the carpet on the passenger side, you might check there as it is a problem child. good luck