Folks,

I am new to this forum and am hoping to get some advice or guideance in troubleshooting an electrical problem in my son's 2005 2WD 3.0 V6 ford Ranger.

The Problem: Truck stopped running, motor turns over, would not start or almost would start. Took to local dealership and at a cost of $200 they diagnosed as fuel pump which they would charge an additional $1200 to replace.

Current status: I replaced the fuel pump yesterday and it woudl still not pump fuel. I brought 12v direct to the pump from the battery and it pumps fuel from tank and by checking in same manner found the fuel pump I pulled from tank also worked so dealership diagnosis was wrong.

I found that the inertia switch under dash connector was rather cooked and somewhat melted so I wired-nutted the two wires together. What I get now to the fuel pump is 7.6 volts only and pump does not turn on.

I checked fuel pump relay and it is turning on with key going on and off. I went as far as cutting the wire from the fuel pump relay and running it direct to the fuel pump to see if it would turn the pump on.off with the key and using the relay and fuse solution but no go. I have what I think is a short in the harness from the relay to the inertia switch wires.

Any idea how to troubleshoot this?

Check all the fuses. Some are under the hood and some in the side of the dash.

I've never heard of an inertia cutoff switch getting melted so you may have wiring problems in lots of places...

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1998 ranger extended cab, 2wd, 4.0 ohv, 5 speed, sony xploid 52 4 way watt radio, 2 pair of pioneer 240 watt speakers, Cobra 29 LX LCD CB radio pushing 100 watts, k&n air filter, 15 inch exploder wheels, dual exhaust with 4 inch stainless tips, 2 12 inch subs with a 1000 watt amp just for the hell of it!

new project: dirt track modified racing at the local saturday night track.

I would start with the wires around the inertia switch to see if they are compromised
roscoe

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roscoe 0202
hi newb here truck 94 b4000 mazda aka ranger
truck is stock just runaround
have project bronco II
i'm 74 and retired
roscoe

I stopped reading when the OP wrote that the dealership charged $200 to diagnose a fuel pump problem.

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Thanks gents for the suggestions.

Tomorrow night after work I am going to hit it again checking for a short. I have isolated "I believe" the section of the harness with the short....inertia switch to under-hood relay output.

My biggest concern regarding this segment of the harness from the inertia switch to under-hood relay output is if anything else by design intention is connected to this wire segment as part of the fuel circuit. I am thinking of trying a bypass from the under-hood relay output to the output side of the inertia switch to see what that that does. Anybody have access to the fuel pump power schematic?

Any other suggestions as the main harness is long under the hood and well protected with no signs of damage anywhere so baffled where short could be occuring.

One question for the collective of folks out there, is there anything tied to the output of the fuel pump relay other than the fuel pump? I thought when I was scanning the internet last night I saw a schematic from an earlier year ford Ranger and that this power rail also went to the engine fuel priming circuit? Anybody able to share any data reflecting what this circuit powers? Thanks a bunch in advance. Greg

visualbits.net/Car%20Stuff/Ford%20Ranger%202001-2008/2005%20WIRING.pdf

visualbits.net/Car%20Stuff/Ford%20Ranger%202001-2008/

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1998 Ranger XLT Super Cab 4.0 ohv v6 - 5r55E automatic Trans - 8.8 with 3.55gears - Toreador Red Clear Coat Metallic -Explorer Sport Trac White Faced Gage Cluster -2006 Mirror Swap-16" Mustang wheels with 215-65-16" Falken Tires

Thanks TXGasRacer! I appreciate the schematics.

Are the numbers on the schematics on left and right sides of pages page numbers that a circuit goes to or an offpage circuit reference number? On page 16 of wiring, the circuit I am chasing "DK GRN/YEL" takes me to inseria switch which I backed into when I reverse engineered the wiring two nights ago w/o schematic BUT same signal "DK GRN/YEL" also goes to a 28 which if I follow it as a page number is a ground and makes no sense this 12v line would go to a ground directly.

Any further advice is very much appreciated?