Electrical problem!!

[C-Bear]

Hey ya'll. 98' Ranger 3.0 2WD XLT
Truck can't stay running, battery is just draining like crazy. Took both the battery and alternator to get tested. Both are good as new. For the time I can keep it running, I started pulling out fuses, as soon as I pulled out fuse 9 from the power distribution box, the electrical tester thing showed that the truck was actually starting to charge up. Now the thing that sucks is fuse 9 goes to the fuel pump and a rap module. Where is the rap module located? I know it is supposed to be for a security system, yet I have manual locks and windows, and as far as I know no security system. Where can I find this module if I were to have one???

 

[RonD]

In '98 Ranger RAP module should be behind drivers seat in a trim panel.
But you probably don't have one, but that doesn't mean the wires are not there and that they are shorting out.

You should see the fuel pump Relay in that same fuse box, pull it out and see if battery drain goes away, like it does when you pull #9 fuse, if so fuel pump could be going bad, drawing too many amps.

 

[Earl43P]

The Location Page 152-11 of the EVTM lists it at LH rear corner of the cab, but the diagram on page 151-8 shows it under the passenger side kick panel, just forward of the door. I'd look there first, it's easier!

Fuse 9 feeds 12v At All Times to the RAP module on the White wire with a light blue stripe.

 

[Big Jim M]

Howdy cbear
I am confused by your post. With the amps the alt can put out anything that could possibly use that many amps would quite probably burn your ride to the ground. I recently had a bad alt that I took to have it checked by the local parts house. They said it was good! I put it back into service and the same battery drain kept happening. So I purchased a new one and the battery drain went away.
I think the alternator is highly suspect in your case also.
Big Jim

 

[enjr44]

Lurk, because I would like to know how a pulling a 9 amp fuse circuit could start the alternator.

 

[Spott]

I don't know the specs for the 98, but I'm sure you have at least a 100A alternator. Like Jim said, if you've got something drawing a continuous load larger than that alternator can handle, it's enough to smoke the wiring harness (but it would blow a fuse long before that). The only thing that big is the starter, and it has massive wiring and its only on for a few seconds at a time. I really don't think your problem is a short-circuit of that magnitude.

Just for good measure, you should start by checking the wires and connectors for the battery and the alternator, including any little wires running to the alternator (maybe you've got a bad control signal). If they're all good and clean, I'd take the alternator to an electric motor/starter shop. They can do much better and more thorough testing on your alternator than the autozone guys can.