Solved 97 Explorer. Battery good, but no power to vehicle.

[rebesal]

Hello all--have been searching for a thread that may already have the solution I need, but decided just to air it out here.

97 Explorer, AWD, 5.0 L V8. No power to the inside or outside, no lights, gauges, sounds, radio, no solenoid clicks, and of course, no start. Meter shows 12.5 VDC across battery terminals, and 10.8 V at starter relay on left side under hood. Battery leads are tight on battery terminals. Pulled the two big 60 amp fuses; they look good, and show good continuity with meter. Vehicle was running fine until the stopped.
Ideas where to check? Thanks!
Bob

 

[Mbrooks420]

That's a lot of drop. Start ohming out cables with your meter. Check them, and wiggle the cables real good, and check again. Second gens, especially, have an issue with the cables rotting out in the insulation.

 

[rebesal]

That's a lot of drop. Start ohming out cables with your meter. Check them, and wiggle the cables real good, and check again. Second gens, especially, have an issue with the cables rotting out in the insulation.

Was wondering about that big of a drop. Will get meter on it. btw--new at this, so: What defines "second generation?"

 

[Mbrooks420]

95-2001 for the four doors.

 

[rebesal]

95-2001 for the four doors.

Ahhh--thanks.
Bob

 

[imp]

@rebesal ".....12.5 VDC across battery terminals, and 10.8 V at starter relay on left side under hood.":

Yer sayin' that under quiet conditions of no power demand, vehicle just standin' there, between Battery + and ground, VS starter relay Battery connection, (same as Battery +), you measure 10.8 V between starter relay B+ connection and GROUND?

There is ONLY one way that can happen. Current is flowing through the Batt. cable, causing a 1.7 V drop across the cable between batt. and relay. Near impossibility. Need more info.... imp

 

[Mbrooks420]

It's actually very possible, and nothing but basic ohms law. There is excessive resistance due to a bad connection, or cable most likely.

 

[rebesal]

Gents, thanks for the pointers -- Issue resolved!
I took a deeper dive, and with my glasses on.
Meter showed 12VDC across battery and at fender-mounted relay. (Suspect I just hadn't seated the probe well enough before, hence the voltage drop. Also had power through both sides of every fuse in the Power Distribution Panel. Swapped the PCM relay with another per some advice on another thread. With voltage good everywhere, I knew I had a major open circuit-- but had concentrated on the "supply side" without a real look return side....
Removed battery ground lead and replaced it with a battery jumper cable, and everything lit up nicely. Removed the battery lead clamp, cleaned it and cable well--the corrosion was hidden inside the removable clamp. Reinstalled, and I'm back on the road!
Thanks again, all!

 

[swshawaii]

^ So, so common. Thanks for the follow up and solution. .

 

[imp]

It's actually very possible, and nothing but basic ohms law. There is excessive resistance due to a bad connection, or cable most likely.

@Mbrooks420
What you state is absolutely true. However, you failed to grasp my meaning of "No Power Demand", that is, NO CURRENT FLOW through the cable between battery terminal and solenoid terminal, NO CURRENT FLOW, E = I X R, I = 0, therefore NO VOLTAGE drop across cable. imp

 

[Mbrooks420]

I guess I wasn't factoring the very basic fact that we're dealing with DC and it's slightly different than the drop associated with AC due to cable impedance.

 

[imp]

I guess I wasn't factoring the very basic fact that we're dealing with DC and it's slightly different than the drop associated with AC due to cable impedance.

@Mbrooks420
Well, we could delve into the fact that alternators are in reality 3-phase A-C generators, but better save it for a rainy day! imp