99 Ranger with 98 Explorer 5.0 Swap No Speedo/Abs light on

[Mvanaxen]

Hi,

I recently picked up a 99 Ranger(2.5) with a 98 Explorer 5.0 swap. For the most part the conversion looks to be done well but there are a few things that need attention. First, the speedo isn't working and the abs light is on. There is a vss fault code atm. The truck came with rwabs that is still in place but not connected to any wiring harness but they have the explorer 4wabs module plugged into the harness and not connected to the brake system(just sitting against the fender). Any help would be very much appreciated.

TIA,
Mike

 

[franklin2]

You need to figure out what they used that year for a vss. Sounds like the vss is not hooked up yet.

 

[franklin2]

P.S. I just looked at a Chiltons manual, I can't quite figure out where the VSS is located. If you have an electronic transfer case, it will have what they call a OSS (output shaft sensor) on the rear shaft and the front shaft. But I think that is only for the 4x4 computer. Not seeing where the VSS is, though I did find a paragraph talking about the ABS speed sensor in the rearend. So maybe that is your VSS in a 1998 explorer and you need to graft the original truck vss wiring to the 98 explorer vss wiring?

 

[Mvanaxen]

The donor was a 98 Mountaineer 2wd with a 4r70w trans. There appears to be a VSS located on the side of the trans that is connected to the trans harness

 

[Mvanaxen]

If I'm not mistaken the 2.5L Ranger gets it's signal for the speedo from the Gem and the Explorer gets it through the ABS module... I guess I'm trying to get the signal from the Explorer wiring to the Ranger Gem but I also would like to use the Ranger rear wheel ABS if possible.

 

[RonD]

Welcome to TRS

The 1999 Ranger used the rear axle ABS sensor and GEM module to get the correct Speed signal to speedometer, computer and cruise
The 1998 Explorer used the rear axle ABS sensor and the 4WABS module to get the correct speed signal to speedometer, computer and cruise
You probably also have a P0500 code, no speed signal at computer
So they both used the rear axle ABS sensor just used different modules to convert the signal to 8,000ppm(what Ford speedo, computer and cruise needs)

I would assume "they" didn't remove the RABS from Ranger since 4WABS is not hooked up so RABS is the reason for ABS light
And since you have an ABS light AND no speedometer the rear axle ABS sensor may be bad or unplugged
Try replacing it and see if light goes off and speedo starts working again

"They" may have added the 4WABS unit just to do the speed conversion, by passing the GEM, which works but "they" didn't need to, they just needed to add a wire to V8 computer from Rangers GEM speed signal

So you can remove the 4WABS unit if you want to run that wire

 

[Mvanaxen]

Thanks for the Welcome!

I replaced the rear sensor with no luck

 

[Mvanaxen]

I would prefer to stick with the RABS and add the wire to the GEM. What about the RABs to 4WABS wiring?

 

[RonD]

Then you will have to start to go thru the wiring and find out where the signal is being lost

The rear axle ABS sensor should have a red/pink(+) and a green/black(-) wire
These sensors make their own voltage, AC volts, 0.5v to 6vAC based on rpm of rear axle

The voltage is not used, just the frequency of the AC Sine wave and only the "+" 1/2 is used
So the green wire should test as a ground, as it grounded at ABS module and/or GEM

The red/pink wire is the one to test at the devices, for continuity
Should be at the 4WABS module and the GEM, behind radio
On 4WABS
Pin 1 is the green wire
Pin 17 is the red/pink wire

On RABS
Pin 3 is green wire
Pin 10 is Red/pink wire

Unless "they" cut out the RABS module it should still be connected
They may have spliced into the red/pink and green wire, and that splice may be the issue depending on how it was done


Both of these wires are Spliced(factory splice), don't know where Ford did that, and run to the GEM module
Pin 9 is red/pink wire
pin 18 is the green wire

Pin 1 on that same connector is the SPEED OUT wire, grey black, same color wire runs to speedo(pin 1 on 12pin)
To Computer pin 58
To cruise pin 3
Except for the computer this grey/black wire should be hooked up to speedo and cruise, and the computer will have the grey/black wire at pin 58 it will just be hooked up to 4WABS
So "they" spliced into this grey/black wire somewhere if speedo was working

You will need to get a long jumper wire and just go thru and test how the wires are connected now

 

[Mvanaxen]

Is it possible they used the explorer enginge bay harness? If so, could that be part of the problem? I didn't use a meter to check continuity but I used a wire tone tool and have tone at the 4wabs harness and the gem.

 

[Mvanaxen]

Looks like that it may be an explorer bay harness(f87b-1438-j4cpa)... explains the larger connector for the 4WABS. I'm thinking I need to find a harness that matches the RABS. Thouhgts?

 

[Mvanaxen]

Any insight would be greatly appreciated before I swap the engine bay harness.

 

[franklin2]

Any insight would be greatly appreciated before I swap the engine bay harness.

You guys got way over my head quickly with all those bits and pieces. What is your logic for swapping the engine bay harness? I would think the easiest most logical thing to do is make the whole truck a 1998 explorer as far as the wiring. Bumper to bumper. You will have to marry any other wiring method and cut and splice to make it work correct? Or as far as the computer is concerned, make it all 1998 and leave all the lighting and other stuff 1999 ranger. You will have to find a convenient place to make 1998 to 1999 separation that will work. If you need the 1998 4 wheel abs system for the swap to work, then swap in the 4 wheel abs system. Are the brakes larger on a v8 explorer? If they are, then that would be a prudent swap to make.

 

[Mvanaxen]

The harness for the explorer is for 4 wheel abs and my truck is a rear wheel abs. I dont want to have to switch all of the front brakes to abs. Id rather get the rear wheel abs engine bay harness and do a little rewiring.

 

[RonD]

Not sure you have to swap over whole engine harness

Here is a 1998 Ranger RABS diagram, 1999 and 2000 should be the same

And a 1999 4WABS diagram, should be explorer since it has the grey/black going to "speedo"(cluster)

You should be able to match the wires since they are the same just without front wheel sensors