ABS light

[Ben]

My ABS lights on and my MOT is getting dangerously close! It's been on since I took both the front sensors out and put them back in for a hub change. The sensors are around £45 each though

Firstly is there any way of checking the sensors?

Secondly is there any reasonably simple way of making the light come on when I turn the key but then go off as it should when the engine starts?

Thanks

[ginge191]

ditto to this; i'd like to also get an answer for this

[Danny2009]

put a wire from the glow plug light to the abs bulb

[ginge191]

good shout...

any chance of getting a volt meter on your working ABS unit and find out which wire is the light; ie, what wire drops is V after ign on.?

[Ben]

When is the ABS light supposed to turn off then? I thought it turned off when the engine was started, and the glow plug light goes off before that..

[ginge191]

The ABS light should only flash on/off, if it goes out with the glowplug's - it's not a huge issue and technically an MOT pass?

[Ben]

Oh ok so it should go out before the glowies? Could wire it to the oil light possibly that goes out pretty quick. I've not had the clocks apart before but I guess its pretty simple?

[Niall]

Instead of being pikeys and not having working abs (ask Ed about the ill effects of this ), just test them and replace. you can get them on eby for about £20 each.
Unplug the sensor, put your mulitimeter on the pins and set it to vAC and slowly turn the wheel. Everytime a raised part of the ring on the driveshaft passes the sensor, you should get a small voltage. if not or if you just have a constant voltage, they are fooked and need replacing.

[ginge191]

Instead of being pikeys and not having working abs (ask Ed about the ill effects of this ), just test them and replace. you can get them on eby for about £20 each.
Unplug the sensor, put your mulitimeter on the pins and set it to vAC and slowly turn the wheel. Everytime a raised part of the ring on the driveshaft passes the sensor, you should get a small voltage. if not or if you just have a constant voltage, they are fooked and need replacing.

And after testing this, working sensors and the ABS light is still on...?

[Niall]

Broken wiring, dodgy pump. Loads of things

[Toms306]

Ben, are you sure you pushed the ABS sensors as far as they'll go into the hub when you changed them? The air gap between ring and sensor is crucial.

[Frosty]

To be honest guys I would think that something like an ABS light being on should get sorted out properly! At the end of the day ABS is brakes and I think brakes are pretty important. Definitely something that short cuts shouldn't be taken on.

Get it plug into a diagnostic machine and see what fault comes up

[Carlos182]

To be honest guys I would think that something like an ABS light being on should get sorted out properly! At the end of the day ABS is brakes and I think brakes are pretty important. Definitely something that short cuts shouldn't be taken on.

Get it plug into a diagnostic machine and see what fault comes up

ABS isn't the end of the world tbh, IMO ofc.
Not to mention that quite a lot of 306 PH1 had no ABS...

[Toms306]

To be honest guys I would think that something like an ABS light being on should get sorted out properly! At the end of the day ABS is brakes and I think brakes are pretty important. Definitely something that short cuts shouldn't be taken on.

Get it plug into a diagnostic machine and see what fault comes up

ABS isn't the end of the world tbh, IMO ofc.
Not to mention that quite a lot of 306 PH1 had no ABS...

And pov spec phase 2s.... It was locking up on a wet crossroad and narrowly missing a transit van that made me upgrade to a ph3 lol. Personally I wouldn't have another car without, its so useful in panic situations!

[Frosty]

Yeah but if a car has ABS it should work really. The light would be on cuz there is a fault in the ABS system which is to do with the brakes. I wasn't commenting about 306s that don't have ABS.

My point is that if a car has ABS then ideally you would want it to work and when the light is on its telling you there is fault in the system. The light could be on for many different reasons from just a sensor down to something wrong with the ABS pump which could be more serious.

At the end of the day warning lights are there for a reason. That my views any way

[Ben]

Ben, are you sure you pushed the ABS sensors as far as they'll go into the hub when you changed them? The air gap between ring and sensor is crucial.

Yeah they are definitely in correctly I checked that yesterday.

In regards to having no ABS I would certainly prefer to have it in a road car, but the lights been on for around 6 months now and I haven't had a problem at all. If I do end up wiring the light up to the oil light then it will only be temporary and I will sort the ABS before winter kicks in. Really must have an MOT certificate by Saturday though, so I don't really care how it passes at the moment!

[Toms306]

Fair enough then, could check all plugs are clean and tight etc if you haven't already. Theoretically you could wire it to another light but the lights will go out at slightly different times as standard, so if the testers watching well enough it'd be noticeable....I don't expect most are that observant though.


Also, for reference, the ABS system will NOT work at all while the light is illuminated, it defaults to non-ABS when a fault is detected and the light is on. So will be best if you can fix it.

[Ben]

Instead of being pikeys and not having working abs (ask Ed about the ill effects of this ), just test them and replace. you can get them on eby for about £20 each.
Unplug the sensor, put your mulitimeter on the pins and set it to vAC and slowly turn the wheel. Everytime a raised part of the ring on the driveshaft passes the sensor, you should get a small voltage. if not or if you just have a constant voltage, they are fooked and need replacing.

Tried this on three of the four sensors, all with the same result. The reading flickered between around 0.003 to 0.005 v when the wheel was turned slowly. The reading would jump up to around 0.040 when the wheel was turned faster.

Does this indicate that none of them are working? If so the problem must be whatever it is that feeds the sensors?

[Toms306]

The voltage increased as the speed increased, that's how it should be.

Why did you only do 3 of 4? Its probably the 4th one that doesn't work.

[Ben]

It didn't increase and decrease in time with the raised points though. If you turned it point at a time the reading wouldn't change.
Only did three because it was getting dark. I was expecting one of the front ones to be buggered so was only going to test them, but when they both appeared buggered I thought I'd compare with a rear one.