E90 ABS/DSC/Brake - ABS sensor/reluctor ring
Discussion
Hi Guys,
I'm looking after a BMW 325d 2010/60 plate (while owner is abroad now for some 3 years), has been sat on the drive for about 3 years now, used to drive it on weekends where possible, but after a prolonged period of not being driven, it wouldn't start. A friend said he knew a mechanic and would come round to look at it. The mechanic tried to jump start, and after much revving the donor car managed to start it. The mechanic said the battery is nearly dead and needs changing and he took the car to change the battery. He changed the battery and said you've got all these lights on - ABS, DSC, brake etc. The mechanic is adamant that those lights were present when he jump started the car and not after changing the battery.
I'm reading that certain things need to be done after changing a battery - which he hasn't done.
There were no lights the last time I drove the car before the battery went flat.
I didn't want to cause any problems between my friend and his mechanic, I didn't take it any further.
I've been reading around the internet and this forum, and this seems to be quite a common problem and is either the ABS/Speed sensor and/or the reluctor ring. So given that it has been standing for quite a while, this may have corroded the reluctor ring along with moisture.
I took it to one garage who put it through diagnostics and said the computer is reporting an error with both rear ABS sensors. He said to get a pair of ABS sensors and go from there. He didn't even attempt to inspect the abs sensor, even though he had the car up on the ramp - as I was also getting the car serviced - oil/oil filter, fuel filter and air filter.
I had read/seen that sometime the sensor just needs a clean - electrical cleaning fluid or similar - he said he would then charge me double if the cleaning didn't work and the second time round to replace the ABS sensor - so wasn't really happy with his "helpfulness" and he also made out that changing the ABS sensor wasn't a straightforward job. Charged me £20.
Having watched countless youtube vids - it's just one screw to take out to check the state of the abs sensor and could also rotate the hub to inspect the reluctor ring through the abs sensor hole.
Another friend recommended another garage, I took it there, he also just put it through his computer and cleared down all the codes, took it for a drive. He came back and said, not a big problem, but will need it in so we can inspect it, he wouldn't say what the problem is, just it's around the wiring. Only when I pressed him, I said is it the abs sensor or reluctor ring. He then said, in his opinion, it's the reluctor ring, reason being, that when he cleared down the codes and started the engine, no lights came on, only when he took it for a drive, did the lights come on - he said this suggested it is a mechanical one and not an electric fault. If the ABS/DSC/brake lights came on, upon engine start, he said this would indicate an electrical fault and point to the abs sensor.
This garage also didn't inspect the abs sensor and just gave me a print out of the diagnostics which had the following codes: Charged me £20
AOB5, 3F62, 5DC3, 5DB3, 5DE1, 93FB
He said to order reluctor rings off the internet and he will fit them. Cost £80 labour both sides.
To be honest, both garages don't fill with me confidence - you'd think, given the common nature of the problem and how easy it is to inspect the abs sensor they would have at least done this.
So wondering what I should do next, just bite the bullet and order the abs sensor and reluctor ring and just give it to the second garage and get it over and done with.
Or take it to another garage with the sole intention of getting the abs sensor looked and if possible cleaned and check the reluctor ring - seen some vids using compressed air to clean any muck of the reluctor ring.
Another post on here (https://www.pistonheads.com/gassing/topic.asp?h=0&f=72&t=1685870), suggests if reluctor ring has risen due to moisture and now scoring the abs sensor, rather than replacing reluctor ring and hence having to remove drive shaft etc, can simply use a washer (M5) to seat the abs sensor slightly higher. So thinking is this worth a try.
Garages fill me with dread, I've so many bad experiences with them and then leaving the car with them all day - is just pure anxiety - you've no idea what kind of job they are going to do. I've had my car come back with screws missing etc.
Over to you for your experienced advice.
I'm looking after a BMW 325d 2010/60 plate (while owner is abroad now for some 3 years), has been sat on the drive for about 3 years now, used to drive it on weekends where possible, but after a prolonged period of not being driven, it wouldn't start. A friend said he knew a mechanic and would come round to look at it. The mechanic tried to jump start, and after much revving the donor car managed to start it. The mechanic said the battery is nearly dead and needs changing and he took the car to change the battery. He changed the battery and said you've got all these lights on - ABS, DSC, brake etc. The mechanic is adamant that those lights were present when he jump started the car and not after changing the battery.
I'm reading that certain things need to be done after changing a battery - which he hasn't done.
There were no lights the last time I drove the car before the battery went flat.
I didn't want to cause any problems between my friend and his mechanic, I didn't take it any further.
I've been reading around the internet and this forum, and this seems to be quite a common problem and is either the ABS/Speed sensor and/or the reluctor ring. So given that it has been standing for quite a while, this may have corroded the reluctor ring along with moisture.
I took it to one garage who put it through diagnostics and said the computer is reporting an error with both rear ABS sensors. He said to get a pair of ABS sensors and go from there. He didn't even attempt to inspect the abs sensor, even though he had the car up on the ramp - as I was also getting the car serviced - oil/oil filter, fuel filter and air filter.
I had read/seen that sometime the sensor just needs a clean - electrical cleaning fluid or similar - he said he would then charge me double if the cleaning didn't work and the second time round to replace the ABS sensor - so wasn't really happy with his "helpfulness" and he also made out that changing the ABS sensor wasn't a straightforward job. Charged me £20.
Having watched countless youtube vids - it's just one screw to take out to check the state of the abs sensor and could also rotate the hub to inspect the reluctor ring through the abs sensor hole.
Another friend recommended another garage, I took it there, he also just put it through his computer and cleared down all the codes, took it for a drive. He came back and said, not a big problem, but will need it in so we can inspect it, he wouldn't say what the problem is, just it's around the wiring. Only when I pressed him, I said is it the abs sensor or reluctor ring. He then said, in his opinion, it's the reluctor ring, reason being, that when he cleared down the codes and started the engine, no lights came on, only when he took it for a drive, did the lights come on - he said this suggested it is a mechanical one and not an electric fault. If the ABS/DSC/brake lights came on, upon engine start, he said this would indicate an electrical fault and point to the abs sensor.
This garage also didn't inspect the abs sensor and just gave me a print out of the diagnostics which had the following codes: Charged me £20
AOB5, 3F62, 5DC3, 5DB3, 5DE1, 93FB
He said to order reluctor rings off the internet and he will fit them. Cost £80 labour both sides.
To be honest, both garages don't fill with me confidence - you'd think, given the common nature of the problem and how easy it is to inspect the abs sensor they would have at least done this.
So wondering what I should do next, just bite the bullet and order the abs sensor and reluctor ring and just give it to the second garage and get it over and done with.
Or take it to another garage with the sole intention of getting the abs sensor looked and if possible cleaned and check the reluctor ring - seen some vids using compressed air to clean any muck of the reluctor ring.
Another post on here (https://www.pistonheads.com/gassing/topic.asp?h=0&f=72&t=1685870), suggests if reluctor ring has risen due to moisture and now scoring the abs sensor, rather than replacing reluctor ring and hence having to remove drive shaft etc, can simply use a washer (M5) to seat the abs sensor slightly higher. So thinking is this worth a try.
Garages fill me with dread, I've so many bad experiences with them and then leaving the car with them all day - is just pure anxiety - you've no idea what kind of job they are going to do. I've had my car come back with screws missing etc.
Over to you for your experienced advice.
The owner is my brother, he thinks it's fine to just start the car for 15 mins and move the car up and down the driveway and then turn it off. I know my brother won't reimburse me and nor am I looking for him to, I'm just trying to save his car. I'm trying to get it fixed and then hopefully convince him to sell it and save further depreciation.
Keep jump starting a late beemer with a flat battery at your peril these vehicles have very sophisticated and often fragile control units 
(well they certainly will become this way) fit a new battery and a battery minder/conditioner if the vehicle is not used often or you may well have an even bigger problem/s coming your way at best a damaged alternator at worst far worse .......................... 
its certainly the last car I would want to leave unused for long periods ill tell you that 
tell him use it or lose it 
spacing the sensors does work and often give 12 months or so grace but long term drive-shaft replacement is the answer as the cv joint the reluctor ring is mounted on rusts and erodes away (shrinks) so a new ring is like a cock in a sock and the BMW sensors dont allow too much run-out or distance fluctuation on rotation before pinging up the dashboard fairy lights and your back where you started
(well they certainly will become this way) fit a new battery and a battery minder/conditioner if the vehicle is not used often or you may well have an even bigger problem/s coming your way at best a damaged alternator at worst far worse .......................... its certainly the last car I would want to leave unused for long periods ill tell you that tell him use it or lose it spacing the sensors does work and often give 12 months or so grace but long term drive-shaft replacement is the answer as the cv joint the reluctor ring is mounted on rusts and erodes away (shrinks) so a new ring is like a cock in a sock and the BMW sensors dont allow too much run-out or distance fluctuation on rotation before pinging up the dashboard fairy lights and your back where you started Edited by Sardonicus on Monday 9th July 23:16
Sardonicus said:
Keep jump starting a late beemer with a flat battery at your peril these vehicles have very sophisticated and often fragile control units (well they certainly will become this way) fit a new battery and a battery minder/conditioner if the vehicle is not used often or you may well have an even bigger problem/s coming your way at best a damaged alternator at worst .......................... its certainly the last car I would want to leave unused for long periods ill tell you that tell him use it or loose it
Having a read round the forums, this is certainly dawning on me, that jump starting modern cars with fragile ECUs, is not the way to go; it probably shows the level of technical competency of some mechanics. (well they certainly will become this way) fit a new battery and a battery minder/conditioner if the vehicle is not used often or you may well have an even bigger problem/s coming your way at best a damaged alternator at worst .......................... its certainly the last car I would want to leave unused for long periods ill tell you that tell him use it or loose it I'm currently researching battery chargers that charge the battery in a safe way.
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