Attention: TDR Forum Junkies 
Joe,
Here's what I came up with on my 94 gasser. Your 95 diesel has different wiring diagrams, pin locations in the controller and diagnostic connector, but WSS should be the same logic. They can't leave stuff the same for very long, it's what makes this job so much fun.
Your speed sensor should be pins 8 & 9, according to my 95 wiring diagrams. All my voltage readings were done with key on engine off and 12. 33 V at the battery.
Pin 8 is "sensor high"
Pin 9 is "sensor low"
The controller sends . 511 VDC out through the sensor circuit. This DC voltage is typically called a carrier voltage to make the AC signal cleaner and for diagnostics. They run the AC signal (which is wheel speed) over this DC voltage. So, this . 511 VDC passes through a resistor inside the controller the comes out of the controller at pin 8. It then goes through the speed sensor and comes back into the controller at pin 9 and goes to ground. When everything is OK the . 511 VDC is dropped between the internal resistor and the coil of the sensor.
Now for the numbers that I had. I connected my Fluke (set on VDC) on the red/vt (pin 8) wire in the "rolls connector" under the dash. You could back probe pin 8 also.
1. Key on, everything hooked up and normal.
. 274 VDC as some voltage is dropped inside the
controller and some is dropped in the actual
speed sensor as current goes to ground.
Basic "series" circuit.
2. Key on, sensor unplugged and wire hanging open
. 511 VDC as there was no current flow to drop
any of the voltage. I got a code 9 stored.
3. Key on, sensor unplugged and a paperclip
shorting the two termials together
. 009 VDC as all voltage was dropped internally as current was going through only one resistance. I got a code 10 stored.
I recommend you hook up a good digital high impedance meter and monitor this voltage over a period of time. You should see something close to the . 274 VDC (there will be a voltage window that be considered OK. If voltage goes out of this window, either high or low, the appropriate code will set. In your case a code 10 should mean a low resistance. Meaning the voltage should be too low at the measuring point in the controller.
What your controller is "seeing" is low voltage at the measuring point after the internal resistor. Things I feel that will cause this are:
1. Shorted wheel speed sensor (WSS) my resistance
was 1297 ohms at 68 degrees in the shop.
2. Short in the harness, the wht/vt and the red/vt wires are intermittantly contacting each other.
3. Internal CAB (controller) fault, not processing the voltage reading correctly.
One more thing, it took about 10 seconds for the Brake and ABS lights to come on after I created a problem, or if I turned the key on with a problem.
This is long, but I hope this helps you. It took a couple hours but I never minded spending quality time with my rigs (my wife thinks I am a sick person for intentionally making lights come on, then figuring out why stuff works, etc). Plus I learned some neat stuff that I can use for ABS class now.
I will check for replies from you, feel free to ask if you have questions on this.
Wayne
Here's what I came up with on my 94 gasser. Your 95 diesel has different wiring diagrams, pin locations in the controller and diagnostic connector, but WSS should be the same logic. They can't leave stuff the same for very long, it's what makes this job so much fun.
Your speed sensor should be pins 8 & 9, according to my 95 wiring diagrams. All my voltage readings were done with key on engine off and 12. 33 V at the battery.
Pin 8 is "sensor high"
Pin 9 is "sensor low"
The controller sends . 511 VDC out through the sensor circuit. This DC voltage is typically called a carrier voltage to make the AC signal cleaner and for diagnostics. They run the AC signal (which is wheel speed) over this DC voltage. So, this . 511 VDC passes through a resistor inside the controller the comes out of the controller at pin 8. It then goes through the speed sensor and comes back into the controller at pin 9 and goes to ground. When everything is OK the . 511 VDC is dropped between the internal resistor and the coil of the sensor.
Now for the numbers that I had. I connected my Fluke (set on VDC) on the red/vt (pin 8) wire in the "rolls connector" under the dash. You could back probe pin 8 also.
1. Key on, everything hooked up and normal.
. 274 VDC as some voltage is dropped inside the
controller and some is dropped in the actual
speed sensor as current goes to ground.
Basic "series" circuit.
2. Key on, sensor unplugged and wire hanging open
. 511 VDC as there was no current flow to drop
any of the voltage. I got a code 9 stored.
3. Key on, sensor unplugged and a paperclip
shorting the two termials together
. 009 VDC as all voltage was dropped internally as current was going through only one resistance. I got a code 10 stored.
I recommend you hook up a good digital high impedance meter and monitor this voltage over a period of time. You should see something close to the . 274 VDC (there will be a voltage window that be considered OK. If voltage goes out of this window, either high or low, the appropriate code will set. In your case a code 10 should mean a low resistance. Meaning the voltage should be too low at the measuring point in the controller.
What your controller is "seeing" is low voltage at the measuring point after the internal resistor. Things I feel that will cause this are:
1. Shorted wheel speed sensor (WSS) my resistance
was 1297 ohms at 68 degrees in the shop.
2. Short in the harness, the wht/vt and the red/vt wires are intermittantly contacting each other.
3. Internal CAB (controller) fault, not processing the voltage reading correctly.
One more thing, it took about 10 seconds for the Brake and ABS lights to come on after I created a problem, or if I turned the key on with a problem.
This is long, but I hope this helps you. It took a couple hours but I never minded spending quality time with my rigs (my wife thinks I am a sick person for intentionally making lights come on, then figuring out why stuff works, etc). Plus I learned some neat stuff that I can use for ABS class now.
I will check for replies from you, feel free to ask if you have questions on this.
Wayne
