ABS at slow speeds
 

Hi Guys,

I tried searching the forum but nothing came back using ABS as the search string, so here is the issue.

Occasionally I used to get the ABS cut in at low speed, sort of when you pull in to a parking space. Lately this is becoming more frequent and feels like it's the front only (not sure if its both wheels or one as its hard to tell from the sound it makes). It's also happening when pulling up to junctions at sub 20mph sort of speeds, and becoming more frequent.

I'm not sure if its related, but I had a replacement O/S drive shaft fitted around 4 or 5 years back, which came off a donor car as the garage had issues matching the splines either side of the UJ when my original UJ failed.

Could the issue be just a mucky sensor, or a sensor that needs replacing, and if so, is this an easy job for someone with just a set of ramps and a socket set ?

The car is a V70 non turbo 2.5 10v 1999 on an S plate.

TIA

Also, just to add, I have no warning lights on the dash regarding ABS

I've tried searching 'ABS' on the forum before and didn't have any luck, if I remember rightly it's because ABS is too short for the search to work properly.

I've just got over a similar problem with mine after messing with the CV joint, in cleaning it off before I started work I must have brushed away too much of a rusty tooth on the ABS reluctor ring on the joint, the teeth on the ring cause a variation in the magnetic field as they pass the sensor so the ABS knows the wheel is turning, if the wheel stops the ABS gets no signal so releases the brake to let the wheel turn, but the same thing happens if there's a missing tooth (or teeth). Fitting a new ring solved my issues. Might be worth having a look at the reluctor rings on yours especially as the driveshaft is from a donor. A new ring will look like the photo below, my old one was significantly more rusty and crusty :)
https://www.partsforvolvosonline.com...9324_large.jpg

We discussed it recently here Help !! Dither mode on Spending Money

Dave, thanks for the reply.

It sounds like a big job? - is it something that requires the removal of the wheel ? If so I'm stuck as I have no means of supporting the car other than ramps...

Really? What would you do if you got a flat tyre? No, it's not a very big job but it will definitely have to be up on axle stands with the wheel off.

Agree with the above - cleaning or replacement of the front reluctor rings would be my guess for those symptoms - have a look at the thread linked above for more info.

Cheers! :regular_smile:

Yeah, I have a standard jack, but would not work on a car without additional support, so time to invest in a set of stands.

What's involved - any specialist tools needed?

Sorry missed the link - having a look now

Uhmmm Seems a bit above my ability....I'll see if the local garage who welded my exhaust up before Christmas can give me a quote once I've got the parts.

Would these be OK - Claims to be for the V70 1996- 07 front wheel. I presume the parts are standard for the cars in this range

https://www.ukpartsdirect.com/abs-re...ring-1005.html

£20.20 for a pair seems a fair price.....

Hey, Malc, J&R Trading have them listed for £2 each. Axel stands are a must but if you're not comfortable disassembling the hub and removing a driveshaft you could end up doing more damage than good. In this instance it may pay you to give it to a local garage.

On a similar note...back in November my daily S80 failed its yearly NCT inspection on a NS drive shaft bellows and, on closer inspection, I also noticed some fore and aft play in both CV joints so, rather than faff about with CV grease and cones etc. I ordered a complete new shaft from J&R which came with said reluctor ring attached and a new bolt for the hub. £80 all in including shipping to RoI and took about an hour of my time to fit.

My observation on those is that they come with a bottle of 'ABS Ring Retainer', which implies to me that they expect them to be stuck on rather than the usual heat/shrink fit, the rings don't do anything mechanical so I suppose it wouldn't matter.
As I suggested in the other thread if you're getting someone else to do it it may be worth checking CV joint or Driveshaft replacement as while the rings are not too technical to do it would use workshop time which you'd have to pay for.