Advice Required - ABS Questions

[MicroMart]

Hello,

Thank you in advance for any replies and information.

I have looked about this and other forums and there are lots of mixed info out there...

2009 V50 1.6D DRIVe SE Lux

I am having some issued with the dreaded ABS light being on, Anti-Skid messages and an upcoming MOT that will of course be a failure if this fault remains....

After start-up I get the Anti Skid Temporary off message and after driving about 20yds the lights clear.

After driving for around 15 wheel revolutions after lights clear the ABS warning lights and message ABS//anti skid service, etc come back on.

When this issue first started I was able to drive about 7 miles, when the warning lights came on and they would clear after startup and be ok again, but over time the issue became more regular and now it is all the time.

After connecting Vida, I get the following errors.

BCM-0012 Wheel Sensor, left front Mechanical error

After clearing the codes, the BCM-0012 code returns.

The checks I have completed so far are,

1) Replaced the wheel sensors (Did the pair, preventative, due to error message on vida).
2) Cleaned the bearing surface where the sensor tip scans....Looks ok....but ?
3) Cleaned the sensor cable pins and checked cables for issues...Look ok
4) Checked the BCM module block connector, cleaned all contacts and re-seated firmly.
5) Checked the bearing hub bolt was tight and secure.

No change to issue

I have since carried out some tests and would like some clarification on the following and any thoughts on the above?

1) Using a multimeter to measure the ABS sensor plugs that feed the wheel sensors....I get a constant voltage reading of around 11.39v on both sensor plugs when the ignition is switched on....
a, Is this constant voltage correct ?
b, Does this voltage change when the vehicle is running or is it a constant voltage ?

2) Using a multimeter to measure the ABS wheel sensor, i get an Ohm reading of .711 on both sensors.....Is this correct ?

I have read about issues also with the BCM module on some vehicles having dry joint issues.....Would love to check that out but the BCM is located behind the battery box and mounted flush against the bulkhead and looks like access to remove the black module (4 bolts) would require the whole unit to come out by way of disconnecting the brake lines....

My next plan of attack would be to change the left front wheel bearing as the error and tests of correct would seem to indicate there is an issue with the bearing/magnet

what are your thoughts ? and any advice on the above would be appreciated....

Cheers
Micromart

[MicroMart]

Ok,
After further research and question asking at SwedeSpeed....
I am going with this as my next action..

Advice by "VolvoGod"
Here a couple of TJ's for this. Look at ABS light on, TJ.
Probably the wheel bearing has walked some.
The front wheel bearings on P1 and P3's are pressed in only, no snap ring to hold in place. Replace the wheel bearing, if walked. Use lock tite on outside of new wheel bearing before pressing in place.
The ABS hub install TJ shows a kit to keep the new wheel bearing from moving. The kit is not cheap.
On the P3 S60 and XC60 the bearing can walk enough for the brake rotor to contact the brake caliper bracket.
https://www.swedespeed.com/attachments/ ... df.151693/
https://www.swedespeed.com/attachments/ ... df.151694/

[MicroMart]

UPDATE:
Fault rectified.
Fix: Bearing drift caused ABS sensor reading fault due to gap.
Bearing replaced/.