OSS sensor wire
Hello new member here, I have a 2001 Ford ranger 2.3lt automatic transmission.
Have a problem with the OSS sensor Output Speed Sensor I don't get any voltage from the wires I did test them and the sensor it self and bought a new one in case that was the issue, I found that the green with yellow wire leads to the pcm but I can't find the brown or gray with red wire anywhere I found some wires that look like that one at the pcm but not sure, does anyone had these issue or has the diagram for the harness or pcm that can provide to me so I can locate that wire and try to solve that issue please, thank you in advance for your help.

 

OSS, like VSS or ABS, sensors generate their own voltage, its AC volts, 0.5vAC to 8vAC depending on tone wheels speed

These are Variable Reluctance sensors, VR sensors, work like this: https://encrypted-tbn0.gstatic.com/i...f5Msg&usqp=CAU

As the "target gear"(tone wheel) rotates each "tooth" that passes by the sensor cause it to generate an AC pulse, the faster the spin the faster the pulses and the higher the AC volts
The AC Volts are not used, the pulses are, the Sine Wave
Usually just the positive half of Sine wave is used, so one wire on a VR sensor is often a Ground

So switch your meter to AC volts
And with rear wheels off the ground, put trans in gear so output shaft(drive shaft) is turning, and you should see AC volts from the 2 wires

OSS wires run to the computer(PCM), OSS was first used starting in 2001 with Rangers
PCM then converts the 30,000 pulse OSS signal to an 8,000 pulse signal and sends that out to the speedometer/odometer, and Cruise, also to GEM and 4x4 module(if so equipped)

 

Hi Ron I am trying to diagnose a similar issue with my 2001 ranger, however mine is a bit unique. I have an aftermarket C4 transmission and an old ford 9 inch rear differential, so my 108 tooth tone ring is not present nor is the internal ring located on the transmission that the OSS reads.

I have tried to simulate the signal by laser cutting a ring for the OSS with the same number of teeth which I fastened to the output flange on my transmission, but have not had luck with getting my speedometer to work which is throwing a CEL for the OSS.

Would the absense of the 108t tone ring be contributing to the problem? Or is that not required?

Any suggestions would be greatly appreciated!

 

Welcome to the forum

VSS and OSS are variable reluctance sensors, they generate their own AC Voltage

So you are using a 2001 Ranger manual transmission computer?

C4 2WD trans should have the hook up for speedometer cable in tail shaft housing which can be used with VSS, plug and play for speedometer
Most C4s had the DRIVE gear machined onto the output shaft, 7 tooth usually

The Unit you put in the hole looks like this: https://www.therangerstation.com/tec...s_withgear.JPG
And this: https://www.therangerstation.com/tec...peedsensor.gif

Has 2 wire plug in for VSS part, and speedo cable hook up which you don't use/need
Used from 1986 thru 1997 in most Fords that got engine computers/fuel injection, so not hard to find, pretty much one size fits all
Driven Gear is of course changeable to calibrate speedometer

If you have a 2001 Ranger computer then you could hook the OSS sensor wires to the VSS to get rid of the code, but it is the wrong pulse count, so might still get a code but not sure


Your 108 tooth tone ring was for rear axle ABS sensor, so not the same as OSS sensor in a transmission, which is 24 teeth, actually "nodes"/bumps, lol
So you could skip the VSS and do a 24 tooth tone ring for OSS sensor, this produces about 32K PPM(pulses per mile)

The computer gets the OSS PPM and reduces it down to 8K PPM to send out to speedo and cruise

The trans mounted VSS does 8K PPM as is so direct hook up to speedometer and cruise

If OSS was also hooked up to the VSS then when you where going 40MPH it would think you are going 10MPH, but in a manual trans computer that should not effect anything since its not shifting gears, speed is not used for fuel mix at all, ever

The OSS is already wired to computer, so you just need the 32K PPM
The VSS would require new wiring, but just to the Computer as it has the speed OUT to speedo and cruise

 

Thanks for all this information, I can tell this forum is full of great knowledge already. Not sure if I should be starting my own thread for this?

To give you the full story, it started out as a 2001 4.0 SOHC 4x4. I wanted to build an offroad prerunner style truck so I tore out the 5r55e and transfer case as well as the 8.8 housing and abs system. The 4.0 SOHC remains in the truck and the transmission/Tcase was replaced with a C4 transmission w/ manual valve body and rear differential is now an old 9 inch

Once everything was running I had it tuned to accept the new manual valve body transmission and the guy that tuned it told me my speedometer would not work and he was unable to clear the CEL, but the truck runs and drives just fine. Problem is I need it smogged and CA will not pass it for the CEL.

I will check out the tail shaft for this gear feature and see about using one of those VSS or even swapping the sensor wires to the VSS to potentially kill the code for now.

 

4x4 will have the speedometer cable hook up on transfer case if its a pre-1998 model transfer case, the 2001 Ranger transfer case wouldn't have it

What is the exact code?

So the programmer deleted Automatic trans software

Dana 20 was popular with C4s, it can use a VSS, hook up seen here: https://classicbroncos.com/img/tranny_tcase_5.jpg

But as said wiring is already there for an OSS you just need the 24 tooth tone wheel

 

Thank you for your help!

I'm assuming I was using the incorrect sensor this whole time or the one I was using was actually defective. When you said swap the wiring and "The trans mounted VSS does 8K PPM as is so direct hook up to speedometer and cruise" I tried that and now the speedometer and odometer work almost exact to my GPS speed.
This is the sensor that is reading my 8 tooth tone ring I made. Its also worth stating I am running 4.56 gearing
https://m.media-amazon.com/images/I/..._AC_SX679_.jpg

The code was P0720.

Going to run the truck to get all readiness completed and get her a smog test.

 

Good work