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gorj
08-11-2017, 08:18 AM
Had an ABS light come on. Ran VIDA and it showed a defective right front sensor. Replaced sensor. Cleared code again and the fault pops back up. So I swapped the left sensor with the right sensor, cleared fault code again and the same code about the right sensor being incorrect component pops up. Anyone with a suggestion?

hoonk
08-11-2017, 12:17 PM
Damaged tone ring, or have seen loose axle bolts cause rf codes (cv joint slides in a little, sensor does not line up w tone ring), wiring to the sensor or a bad control unit. Have never seen a bad sensor, but have replaced hundreds of control units on earlier cars.

gorj
08-13-2017, 02:18 PM
Damaged tone ring, or have seen loose axle bolts cause rf codes (cv joint slides in a little, sensor does not line up w tone ring), wiring to the sensor or a bad control unit. Have never seen a bad sensor, but have replaced hundreds of control units on earlier cars.

Since you seem to be the only one in three forums that seems to have a grasp on this issue I will tell you more of the story. About two weeks ago I replace a noisy right front wheel bearing. I noticed the new bearing di not have the magnetic ring on the transmission side of the bearing. All it had was a plastic dust shield with Volvo printed on it and a Volvo part number. So I removed the magnetic seal from the old bearing, took off the plastic dust ring on the new bearing and installed it. After reinstalling the steering knuckle I re installed the sensor and plugged it in. Put the tire back on and went for a test ride. The new bearing was quiet. But the ABS light was on. So back into the shop and hooked up my VIDA diagnostics. It gave me the sensor error. The rest you know. A local mechanic tells me he had in the past received bad bearings that did not have the correct magnetic bearings on the outer surface to activate the sensor. I had never heard of that. Earlier Volvo had a tone ring that looked like a small toothed gear. This one does not. I think Volvo changes things up every so many years so they can sell more parts!!

hoonk
08-14-2017, 06:15 AM
You have the newer style press in wheel bearing with as you said an internal tone ring - have not had to replace any of those yet. But have seen abs problems on the C70 with the same design. The wheel bearings have no retainer and can move in the housing - The c70 bearings moved and created a lack of signal - pressing the bearing back into position restored that signal.

In your case - bad bearing has abs signal, new bearing has no abs signal - if it's pressed in all the way I'd say you had a bad new wheel bearing.

gorj
08-14-2017, 08:06 AM
You have the newer style press in wheel bearing with as you said an internal tone ring - have not had to replace any of those yet. But have seen abs problems on the C70 with the same design. The wheel bearings have no retainer and can move in the housing - The c70 bearings moved and created a lack of signal - pressing the bearing back into position restored that signal.

In your case - bad bearing has abs signal, new bearing has no abs signal - if it's pressed in all the way I'd say you had a bad new wheel bearing.

So you are saying that even when in a static position the sensor is picking up a signal from the bearing?

I will check the bearing. Thanks.

Steve H.
08-16-2017, 01:45 PM
This bearing shows a ring that comes with it. Is this the type of ring that you transferred to the new bearing? https://www.rockauto.com/en/moreinfo.php?pk=5556429&cc=1441397&jsn=333

gorj
08-19-2017, 05:03 PM
This bearing shows a ring that comes with it. Is this the type of ring that you transferred to the new bearing? https://www.rockauto.com/en/moreinfo.php?pk=5556429&cc=1441397&jsn=333

No. My bearing came with that ring also. But it is only a plastic dust seal. The ring I took from the old bearing was metal and was magnetized. But now I believe it does not work either and that the bearings on the transmission side need to be magnetized and the new bearing I installed is not. From what I read, there is a possibility the bearing is installed backwards and the magnetized bearings face the hub! So I believe I am going to have to do the job again with new bearings.

gorj
08-30-2017, 12:58 PM
With the suggestions from several in the forums and local mechanics I replace the right front wheel bearing again. I purchased this one from another supplier who said it had the proper tone ring in the proper place. Got everything buttoned back up and here is the message I get from vida-dice: BCM-C00344A Right Front Wheel Speed Sensor - System Internal Failures - Incorrect component installed.
PBM-U012100 Lost Communications With Brake control module - Alogorithm Based Failure - Event information
I am stumped.

Dimmur
09-06-2017, 09:38 AM
Hi, new member, old to Volvos!

Do you purcased genuine Volvo bearings? The type that comes with the hubflange pressed in? It is WERY importent that the bearing is pressed comletely to the bottom of its "seat". The bearing must be pressed so far in that it is seated below the edge of the knocklehouse. If the bearing is at the same level as the edge of the knocklehouse, you will get abs sensor fault.

Steve H.
09-15-2017, 06:06 PM
Any update to the resolution of this problem?