DSC Sensor 2 change - please help!

[P3dro]

Hello all,

I seem to have a very slight weep of brake fluid coming from the bottom of the number 2 DSC sensor where it meets the brake master cylinder (the one closer to the servo)

It's a really tight spot with barely any room to move in there - i dont have a spanner large, long or cranked enough to fit so I tried to nip it up with some long-nose adjustable grippers but no joy!

I'm thinking i may need to make some more room to get at it to tighten or replace but I cant find any guides or advice on youtube etc.

Does anyone know if there is a specific tool for the job that allow in-situ replacement or are there a few key parts that need to be removed first to allow access?

Any help would be greatly appreciated....I'm fairly competent with a set of tools but dont know this car very well at all

Thanks,

P

[momo]

Had mine replaced by a garage last year but I stuck around to watch. They wedged the brake pedal, then removed the air pipe to the servo and then removed the brake pipes to get clearance for a spanner. There was only minimal spillage which they mopped up with a cloth. Obviously this way means doing a full system bleed at the end.

I've heard others using a normal spanner but either cut short or a stubby spanner.

Edited August 21, 2018 by momo

[B.Merr]

6 hours ago, P3dro said:

Does anyone know if there is a specific tool for the job that allow in-situ replacement or are there a few key parts that need to be removed first to allow access?

 

Hi - A 27mm open ended/ring spanner is useful to loosen the sensor. I had a go at this last year and all is still well with my 320d. See the last couple of posts in this thread for a description of steps taken to replace: http://www.e46zone.com/forum/topic/65034-the-dsc-trio-3-lights-on-dash-the-basics-done-but-still-no-luck/?tab=comments#comment-926802

[P3dro]

Momo & B.Merr - thanks so much for your speedy replies!

I have that size spanner on order and plan to carry out your suggested methods (both quite similar in parts) and then book in for a bleed with my local garage. 

Super helpful guys, really appreciate it!

P

[ian332isport]

On 22/08/2018 at 12:15, P3dro said:

and then book in for a bleed with my local garage. 

You won't really be able to drive the car until the brakes have been blead. At best, the pedal will be a bit spongy, at worst, it will hit the floor.

[Tim-Ci]

I got lucky with a pair of mole grips when I replaced my DSC sensor recently - the top one (not sure if this is 1 or 2). I kept moderate pressure on the brake pedal with an axle stand wedged between the pedal and front seat (engine off) and quickly swapped the sensors so air entry was minimal or nonexistant, the pedal feels fine, although I will change the fluid and do the DIS software ABS system bleed thing soon just to be sure. At least I have DSC now that winter is approaching.

I fitted this type of sensor from EBay, for a bargain price: https://www.ebay.co.uk/itm/OEM-ABS-DSC-Pressure-Sensor-For-BMW-E46-3-series-34521164458-UK-NEW-ORIGINAL/291889783264?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

It looks VERY similar to the genuine one, and gives exactly the same readings as the other (factory fit) sensor, so all is well now.

I know the advice is normally to steer clear of non genuine for pretty mcuh all E46 sensors, but this one seems fine, and at £22 I am willing to see how it performs. I can check the pressure data on my OBD tool to have confidence it continues to work well.

I was quite careful in tightentening the DSC sensor, as it looks like it screws into aluminium, I did it up firmly but didn't carry on cranking it once it felt firmly tightened. I would estimate I put about 30Nm of torque on it.

[momo]

18 minutes ago, Tim-Ci said:

I got lucky with a pair of mole grips when I replaced my DSC sensor recently - the top one (not sure if this is 1 or 2). I kept moderate pressure on the brake pedal with an axle stand wedged between the pedal and front seat (engine off) and quickly swapped the sensors so air entry was minimal or nonexistant, the pedal feels fine, although I will change the fluid and do the DIS software ABS system bleed thing soon just to be sure. At least I have DSC now that winter is approaching.

I fitted this type of sensor from EBay, for a bargain price: https://www.ebay.co.uk/itm/OEM-ABS-DSC-Pressure-Sensor-For-BMW-E46-3-series-34521164458-UK-NEW-ORIGINAL/291889783264?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

It looks VERY similar to the genuine one, and gives exactly the same readings as the other (factory fit) sensor, so all is well now.

I know the advice is normally to steer clear of non genuine for pretty mcuh all E46 sensors, but this one seems fine, and at £22 I am willing to see how it performs. I can check the pressure data on my OBD tool to have confidence it continues to work well.

I was quite careful in tightentening the DSC sensor, as it looks like it screws into aluminium, I did it up firmly but didn't carry on cranking it once it felt firmly tightened. I would estimate I put about 30Nm of torque on it.

Did yours come with that ATE branding on the part?

[Tim-Ci]

Just now, momo said:

Did yours come with that ATE branding on the part?

No, I think it was unbranded. However, the look of the materials and finish looked so very similar to the genuine ones it wouldn't surprise me if they're rolling off the same production line. The quality of the sensor reading all the way from no pedal pressure to loads of pedal pressure impresses me though, it's pretty much identical to the other (genuine) sensor.

[momo]

Was going to say the genuine/OEM ones are ATE branded. I thought you may have stumbled on an aftermarket seller of them! They're ~£100 each from BMW (I changed both of mine for genuine BMW ones in 2017).

[Tim-Ci]

Well perhaps the branding is stamped in after moulding?. I think this could be a nice find. The build quality and pressure reading produced compared to the genuine one impresses me, it really is pretty much identical (within say 1%) all the way from the 0-150bar that I have seen reported. It does mention genuine in the EBay ad, that could be a clue as to the source of the sensors.

Usually there a no short cuts or cheap options with E46 sensors, but this might be one I hope!

Edited September 28, 2018 by Tim-Ci

[momo]

Tbh I think the issue with the cheaper ones isn't that they don't work or give correct readings, it's that they don't seem to last for long.

Time will tell on that one..

[Tim-Ci]

Yes time will tell. If I get a few years out of it I will be happy, and it will be a good saving over a BMW sensor which don't always have a satisfactory lifespan either in my opinion.