ABS light

[dw8]

Had a new front right wheel bearing put in. Upon driving away from the garage the ABS light came on. Had the light read and it stated no speed sensor signal from fr. Ordered new sensor and installed it. Cleared the ABS light and it immediately came back saying the exact same code. Going to test the continuity of the harness tonight. Any suggestions?

On a sidenote. The bearing was definitely bad, but the noise still is there.

 

[njaremka]

what does the shop have to say about it? seems suspicious that they replaced a wheel bearing, and now you are having ABS issues.

 

[dw8]

He is as baffled as me.

 

[flcruising]

According to section '04-13-13' of the FSM, you can replace the front wheel ABS sensors, but the magnetic pickup is integral to the hub which may need replacing if it was damaged during bearing replacement (which sounds like your issue).

 

[dw8]

You are referring to part number 1? And FSM is the factory service manual?

 

[skyhawk]

could be mis adjustment. i.e. encoder 'teeth' not sensed by the sensor. remove sensor, look through the hole, see encoder 'teeth'. then go to the other wheel, remove sensor, check the hole. compare. They should look the same. If yes, how far is the new sensor face from the encoder? compare.

 

[dw8]

Your image didn't work.

I looked down through the holes of both front wheels last night. Both looked the same. Didn't see anything on either side that looked like "teeth". Will have to get both wheels off the ground and spin the hub in neutral until I see something.

 

[njaremka]

the "teeth" are going to be right under the speed sensor, and you wont be able to see them without taking the wheel off. you might even have to take the brake rotor off.

 

[flcruising]

You are referring to part number 1? And FSM is the factory service manual?

Yes and yes.

skyhawk - There is no adjust-ablility of the sensor, or 'teeth' present. The sensor works off of a magnetic pickup from a rubber ring. One would assume that the mechanic has inspected the hole and cleaned out any debris if present.

 

[dw8]

I do remove the wheel when I look down in the speed sensor hole. This is the diagram the FSM shows of the sensor.

 

[njaremka]

ok, i wasn't clear as to how the 5 ABS sensors are. looks like the bearing replacement is the cause of the sensor not working correctly, as it appears that the sensor rotor is mounted to the bearing assembly.

 

[Robotazky]

dw8, I highly recommend that you either do the work yourself or take it to the dealer. This problem you have is because the mechanic didn't bother reading the directions for this repair. It's getting harder and harder to find mechanics that read instructions. It's not that they can't do it right, it's that they won't. If I take one of my older cars to a regular mechanic because I don't have time or the proper tools, I take copies out of the manufacturer's shop manual and tell the mechanic to follow the instructions or I'm not paying. Rude, but it's better than being ripped off by a douche. Now I have a handful of guys who know when I come in that I'm not playing and to fix it right. I even go so far as to tell them I want the proper torques on every screw unless it's trim or something.

 

[dw8]

I trust the mechanic I took it to. And he is on board for getting it fixed properly. I was doing more reading and found the magnetic strip is in the wheel bearing itself. I didn't buy my wheel bearing from Mazda. I bought a National brand from where I work (Advance Auto). I wonder is National doesn't put the magnetic strip in the bearing? Just spoke with Federal-Mogul tech support. The magnetic strip is incorporated. So my bearing must be installed backwards.

 

[flcruising]

Your right, '03-11-6' of the Workshop Manual addresses this. The mechanic should be able to flip the bearing around for no charge. But then, this may be why you are still having the same noise issue, since the bearings are angular, they probably aren't preloaded properly when installed in reverse..? Hopefully no damage was done.

 

[Robotazky]

I trust the mechanic I took it to. And he is on board for getting it fixed properly. I was doing more reading and found the magnetic strip is in the wheel bearing itself. I didn't buy my wheel bearing from Mazda. I bought a National brand from where I work (Advance Auto). I wonder is National doesn't put the magnetic strip in the bearing? Just spoke with Federal-Mogul tech support. The magnetic strip is incorporated. So my bearing must be installed backwards.

Your mechanic put the bearing in backwards and you trust him? OK.

 

[skyhawk]

Yes and yes.

skyhawk - There is no adjust-ablility of the sensor, or 'teeth' present. The sensor works off of a magnetic pickup from a rubber ring. One would assume that the mechanic has inspected the hole and cleaned out any debris if present.

thanks flcruising. the more I like my mazda5 now. I thought it is still using the 'teeth' like the cars I see in the junk yeard. this makes the abs more reliable with magnets themselves rotating beside the sensor.

 

[dw8]

Time for a follow up on this. Bearing #2 installed yesterday. ABS light is now out and the cruise control is working. But I still have the noise. Going to rotate the tires again and see if that makes a difference.

 

[dw8]

Back from the dead! I have rotated the tires and still have that sound. Symptoms are even the same. Turn the wheel slightly to the left and it is whisper quiet. With the wheels straight and or moved to the right it growls. I can't possibly have had 2 bad bearings. What is the next bearing in line to look at? The only one I can see is the one in the intermediate shaft.

 

[flcruising]

Check your tire wear pattern and the alignment.