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Hello, I have just recently purchased a 2006 subaru outback 2.5i wagon for cheap as it needs some work. The ABS light is on ass well as the "ERR SS" On the odometer which as I understand means the computer knows that this is a wheel speed sensor issue. I forget the exact code it is setting but I can say for sure that that the description is "Right rear wheel speed sensor circuit open/short" some measurements taken so far are up the computer on the green and blue wires reading about 10.6V on the green wire and pretty much nothing on the blue wire. Down at the sensor at the harness I'm reading pretty much nothing on either wire. I have unplugged the harness at the computer and ohmed the wire both at the computer and at the sensor harness and I'm getting OL on the smallest scale. When I pull the harness and then sort of "push" the wires back I get some resistance measurements making me think short to ground. So after getting these readings a couple of times, careful not to touch ground with my tpin and with the harness unplugged from the sensor of course, I went under the seat and removed the grommet from the body and pulled the harness though, to inspect for rubbed wire. The grommet is in good shape, no chance that this is where the short could be. After inspecting for a couple minutes and not finding anything, I rechecked the wire with the ohm meter to find OL no matter how I move the harness around, so I figure, OK, based on everything so far, if I plug the harness back into the ABS computer with the key on, I should have that 10.6 or something close on that wire down at the harness in the back at the sensor. Wrong. Still no voltage. Not sure how to approach this now... Also, according to the diagram that I pulled from Alldata, the power supply should be on the blue wire, not the green, so I'm unsure how much I can trust any of that.. Adding to my confusion.
Go to the opposite wheel and disconnect the sensor plug and teste harness side! Like that you make shore how it works.
if I understand you have voltage on the unit pins but not on other side (harness side) with sensor unpluged!? So you have a problem with the wire(s).
I don't know the ABS on this vehicle but on a lot of cars with so called active wheel speed sensors unplugged tests don't give you any help because the on switch on the ABS module performs a self-test and part of that self-test is an electrical on each wheel sensor and its' wiring, if the self-test fails because of a wheels sensor that is out of specification or short or open the power supply to that wheel sensor is shut off to protect the ABS computer. Diagnosing these systems without a an oscilloscope and a scantool that will read live data from the ABS module can be difficult. One simple test is to clear the code turn then ignition back on if the code pops straight back up before the car is moved it is an electrical fault in the sensor or the wiring. If the code only comes back after the car has been drive 20 yards or so then it is likely a problem with the activation of the sensor --- an issue related to the sensor & wheel bearing (or older style toothed reluctor ring). The gap between he sensor and the wheel bearing is very critical too wide and the sensor won't switch hi-lo-hi-lo or will skip segments.
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Update on this. I believe you are correct in saying that the computer will stop sending feed voltage if an open or short is detected. I found that on my feed wire I would get almost battery voltage then after 5 seconds it would go away. Next I ohmed the sensor itself unplugged and got OL. Bad sensor. Installed a new sensor and now I am getting a new code simply regarding the RR signal. I do have access to high end scan tool equipment so i watched the signal or input and the RR will intermittently give a signal, which is the wrong speed, example I was going 50mph and the sensor was giving me sparatic inputs of anything from 5mph to 20 mph. Also sounds like the bearing itself growls, no play but very noisy. Does anyone know what the "reluctor rings" look like on these? On the axle or the bearing I can't see anything that looks like a reluctor. Beings that the bearing is noisy I think I want to swap that out..
Last edit: 6 years 3 months ago by Tmusser96. Reason: Typo
The reluctor ring will be embedded in the bearing oil seal, the clearance gap between the seal and the sensor is really critical--- too big a gap and the square wave signal gets lost. Sometimes this is caused by rust underneath the sensor -- "rust jacking" the sensor away from the bearing but often it is just bearing wear and tear,
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Fixed! New wheel bearing fixed the issue ABS is working great, signal looks good. I examined the old bearing and grease had crept out from behind the grease seal and coated the seal. Not surprised that this couldn't produce a good signal. Nice quiet smooth bearing and I'm all smooth sailing! Thanks for the help
