86 Bronco no voltage to fuel pump, a little help please

Ok, here goes: on my 86 Bronco (302 AOD) it decided to just up and stop on me. I tried bypassing the fuel inertia switch, have replaced the fuel relay switch, the fuel pump(first thing I did), the entire fuse panel, and
the computer. I've checked the ignition module and physically checked ALL the wiring (I removed the front dash!) I've got 1.72v all across the ECC relay. I'm supposed to have 12v at the hot wire and 12 at the igniton when the key is on, but got the 1.72v I've checked all the ground wires I can find, and all other systems work fine, just nothing at the fuel pump. Any suggestions would be greatly appreciated. Allen snipped-for-privacy@yahoo.com
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I can't be sure that you are esting voltage drops properly but your testing indicates a some kind of power supply concern. This could be either hot side or ground side related. Brush up on voltage drop testing and repeat the tests. While the explanation may be confusng, vlt drops are easy to perform and do tell a story if read correctly.

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I had an identical problem on my Father-in-Law's 86 Bronco. Turns out that one of the negative for the fuel pump is fed straight from the negative battery terminal. It was one of those smaller leads coming from the post clamp. Anyway, it was simply a crimp connector that wasn't tight enough and over time had lost continuity all together.
CJB

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Frankly, I found it doing a wiggle test, so I wasn't sure what exactly was fed by that neg. I know the fuel pump relay, and therefore the fuel pump, wouldn't energize when the connector was open, which was much of the time.
It's interesting that before I found the problem, a garage told my father-in-law that he needed a new computer for that truck. I guess they couldn't get any output from the computer, and therefore diagnosed the computer as dead.
One more thing I should mention too. I had an 88 Crown Vic that would have used a similar relay to feed the power to the fuel pump. I went so far as to replace the fuel pump (like an idiot) and found that the new pump wouldn't work either. Turns out the relay harness itself had an intermittent connection.
CJB
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CJB wrote:

that ground.... it grounds the negative side of the main ecm relay coil .. no ground no ecm bought a truck years ago .. didnt run paid small sum of money ... fixed ground and presto
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Rob wrote:

It's funny, sort of. Most folks will keep the B+ side (the wiring and connectors you see) spotless, but don't understand the B- (body ground) side of things. The entire body\frame\engine of the vehicle is the return path to the source (battery). Years ago an old timer explained it to me simply. The whole car is one big cable going back to the battery. If the path is blocked or open, you got problems. I've never forgotten that.
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