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I need to wire the vss signal directly into the back of my psom. My 95 has a short somewhere in the wiring that I cant track down. Happened after MAF/ sterling swap. Everything worked before hand so i know the sender on top of the axle is good, psom is good. Just need to know what color wires to splice into on the back of the psom to get my spedo back. Thanks:thumbup
 

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I put a 95 maf bronco harness in my 92, removed all the 4WABS wiring, and bypassed the 4WABS control module by connecting together the speed signal wires that were originally run through the control module (2 in / 2 out). Lengthy writeup:http://www.gofastbroncos.com/forum/viewtopic.php?f=14&t=1359

If you're just looking to bypass a missing/bad 4wabs module these are the wires you connect (pin#s referenced are for 4WABS connector, C119):
This procedure is for the above mentioned 95 maf bronco harness but should be the same for any 93-96 4WABS equipped ford truck
 

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yo;
PSOM Wiring Diagram in 96 F Series, 92-95 are Similar Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net

from "Rear Axle Sensor ( love when Ford changes nomencalture from Diagram to diagram!) to PSOM are;

R/PK
& LG/BK

Steve83 wrote, The RABS module won't screw up the speedo or trans the way the 4WABS module can, and even if it goes bad, simply unplugging it removes it from the Gy/Bk circuit.

PSOM for '96 pickups. '92-95 similar.

CHECK SPEED INPUT SIGNAL

NOTE: Only wiring harness end of connector is to be probed.
* Connect Rotunda Digital Volt-Ohmmeter 014-00407 or equivalent to Pin 4 (speed in ) and Pin 5 (speed in -).
* Does the voltage increase smoothly and continuously from 0 to approximately 3.5 volts as vehicle speed increases from 0 to 48 km/h (0 to 30 mph)?
OR:
* If available, a frequency counter may be connected to Pin 4 (Speed in ) and Pin 5 (Speed in -).
* Does the displayed frequency of the signal increase smoothly and continuously from 0 to approximately 667 Hz at approximately 48 km/h (30 mph)?
OR:
* If neither a voltmeter nor frequency counter is available, vehicle speed control may be used as a good indicator. If it works normally, then the speedometer module is at least receiving a speed input signal and the wiring and sensor can be assumed to be good.

Rear axle sensor should read 800-1400 Ohms across the pins, and more than 10 Ohms from the metal shell to either pin
 

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Discussion Starter #6
yo;
PSOM Wiring Diagram in 96 F Series, 92-95 are Similar Source: by Ford via Steve83 (Steve, That dirty old truck) at SuperMotors.net

from "Rear Axle Sensor ( love when Ford changes nomencalture from Diagram to diagram!) to PSOM are;

R/PK
& LG/BK

Steve83 wrote, The RABS module won't screw up the speedo or trans the way the 4WABS module can, and even if it goes bad, simply unplugging it removes it from the Gy/Bk circuit.

PSOM for '96 pickups. '92-95 similar.

CHECK SPEED INPUT SIGNAL

NOTE: Only wiring harness end of connector is to be probed.
* Connect Rotunda Digital Volt-Ohmmeter 014-00407 or equivalent to Pin 4 (speed in ) and Pin 5 (speed in -).
* Does the voltage increase smoothly and continuously from 0 to approximately 3.5 volts as vehicle speed increases from 0 to 48 km/h (0 to 30 mph)?
OR:
* If available, a frequency counter may be connected to Pin 4 (Speed in ) and Pin 5 (Speed in -).
* Does the displayed frequency of the signal increase smoothly and continuously from 0 to approximately 667 Hz at approximately 48 km/h (30 mph)?
OR:
* If neither a voltmeter nor frequency counter is available, vehicle speed control may be used as a good indicator. If it works normally, then the speedometer module is at least receiving a speed input signal and the wiring and sensor can be assumed to be good.

Rear axle sensor should read 800-1400 Ohms across the pins, and more than 10 Ohms from the metal shell to either pin
So I should be able to wire directly in pin 4 and 5?
 

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Miesk you are a vault of knowledge that someone has left open. I am planning to put a vss back into my 89 transfer case to let me run a 14 bolt rear axle and had not yet looked into how to wire up this vss since the 96 harness uses a rear axle vss only. I should be able to simply move the connector but was needing a back up plan should that not work. Now I will just need to calculate what size speedometer gear that I need to make it work. Will be nice to not need a axle with a vss setup.
 

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This is awesome... Going to try using my Cruise control to see if the signal is making it to the PSOM. ( assume cruise control is synonymous with "Vehicle Speed Control") But I'm guessing this wont work.

(checked the connector on the VSS, looks great. The wiring harness under the dash (all three) look good)

But I think I have a power issue, because my Radio stopped receiving power the same time my Speedo, Odom, stopped working. (I have all other instruments and light/dimmer in the cluster, just not a moving speedo, and odom is off)

Checked all my fuses all are good. I did have a blown fuse in the engine compartment box in position c or d, but its been replaced (that wasn't the problem, but could be a symptom...)

I figured the best move is to trace down the power source for the radio (need to figure out which pin on which wiring harness its coming from. Also I'm thinking I can just check at the VSS connector if voltage is going into the sensor? (I would assume if I'm getting anything there that's a good sign. (but unlikely i am)

I would normally just go buy a new VSS, to rule it out... but with the Radio power going out at the same time... Seems to be too coincidental, so I'm willing to bet the power feed to the applicable wiring harness is busted somewhere... (I wish those Supermotor pictures weren't all lost.) Need to figure out which harness to further inspect.

Off to looking for wiring diagrams! (need to get a new Haynes manual, or maybe my Alldata.com for the bronco is still available, but I think it was just a year of access)

if anybody has any support on the subject, I'm all ears... thanks for reading, and sorry to bring up an old post, but out of all the VSS posts, this one seemed to have the best info, so figured it was good to revive instead of starting a new one.

Sorry just realized this wasn't the noob forums...
 

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It will help some if you tell us what year Bronco you have, but I'll make a guess and try to help. You really should start your own thread rather than hijacking @dukedrummer89.
I have a lot of the '94 EVTM which has power distribution and VSS schematics.
Here's the VSS schematic with connector pin numbers:

1996 Ford Bronco '94 EVTM picture | SuperMotors.net


1996 Ford Bronco '94 EVTM picture | SuperMotors.net

Look through the EVTM for the power distribution and radio schematics, power is around page 13, radio about page 130
 
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