where is the ABS light on the dash? ABS not working!

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Rickbmw1984
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Fri May 08, 2009 1:09 pm

Where abouts it the ABS light on the dash? My car failed its mot because the abs light doesnt come on and off on start up. Turns out i didnt have any sensors on the front so ive added them but now i cant see the light to check.

A simple check is to just slam on and see if i skid. The car will not skid but yet i dont feel and judder under the brake pedal.

The car is booked back in for its mot on monday and it needs to pass or im screwed getting to work. if i have sensors in and it isnt working what am i best to do? get a new control unit and pump?

oh my car is a 320se but its got the m20b27 engine just in case it changes anything

Thanks in advance

Richard
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Fri May 08, 2009 2:13 pm

ABS warning light is the orange one

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Rickbmw1984
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Fri May 08, 2009 2:45 pm

hmmm well that doesnt light up on my car but yet i have all the sensors now plugged in....damn it!

any ideas?
gareth
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Fri May 08, 2009 3:01 pm

is the bulb ok?
or removed to hide a previous fault?
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Rickbmw1984
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Fri May 08, 2009 3:35 pm

well im guessing thats why the previous owner had removed the sensors. but saying that he had changed the suspension over so thought he may have just forgotten. It passed the last mot ok and now it fails.

i should check the bulb before going round changing pumps n that!
gareth
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Fri May 08, 2009 8:56 pm

it's possible to get the abs bulb and oil pressure bulb to accidentally light up in the wrong holes should you really need to winkeye
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DanThe
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Fri May 08, 2009 9:27 pm

You could solder some wires onto the back of the oil pressure light bulb, but really it would depend on how well your engine holds oil pressure and when the tester decides to check the abs light
Jon_Bmw
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Fri May 08, 2009 9:31 pm

Dan the shame, you have your front fogs on! :)
bodger
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Fri May 08, 2009 9:35 pm

whats the green light under the fuel gauge for :?
gareth
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Fri May 08, 2009 9:37 pm

bodger wrote:whats the green light under the fuel gauge for :?
the answer beat you to that question.... :mad:
Jon_Bmw wrote:Dan the shame, you have your front fogs on! :)
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bodger
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Fri May 08, 2009 9:40 pm

fog lights are under the mph gauge arnt they
gareth
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Fri May 08, 2009 10:02 pm

so they are... :o:

i've just been out to look at my spare dash cluster in the garage and that light segment is there, is green and has no markings on the lense. on the back of the dash there is a marking showing a circular arrow...

traction control? :P
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DanThe
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Fri May 08, 2009 10:48 pm

Its a special light :wink:
Rickbmw1984
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Wed May 13, 2009 1:47 pm

well just to let you know i went with the oil pressure option and now i have perfect working abs *cough*

Passed my mot now too! after its third fail!

Got pulled by the police driving to collect a drivers seat but a £60 fine is nothing compared to the feeling i now have of having a legal car back on the road :D

So all in all ive had to do the following.

All new discs and pads
handbrake adjustment
emmissions as they were well too high.
drivers seat in secure so new seat put in.
ABS not working so bodged the electrics.
Hardly any bulbs on the car so added all new bulbs all round.
Exhaust was insecure so bracketed that up.

All in all it was worth it as i now have a car that passed with flying colours! haha

Thanks for your help
kman82
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Wed May 27, 2009 3:34 pm

I have an MOT coming up and know for a fact that the ABS bulb has been disconnected as it shows red all the time. I assumed this had been done to get it through a previous MOT. If ABS is fitted to the car does it have to work to pass MOT?
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Brianmoooore
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Thu May 28, 2009 12:40 am

kman82 wrote:I have an MOT coming up and know for a fact that the ABS bulb has been disconnected as it shows red all the time. I assumed this had been done to get it through a previous MOT. If ABS is fitted to the car does it have to work to pass MOT?
No, doesn't have to work, as there's no way of testing it - no road test in a UK MOT test.
The warning light does have to do what it's supposed to do, though.
What EXACTLY does your light do. Most ABS faults are easily cured.
kman82
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Mon Jun 29, 2009 1:04 pm

Brian

Have looked into this fault in more detail after replacing my instrument cluster at the weekend. The ABS light goes off after starting the car then comes back on 20 yards down the road. Assuming a sensor problem.

Have checked the resistance at each connector and the front left didn't give me any reading at all which would suggest the problem lies there?

Whats the next step for me? Theres no obvious signs of cracks or tears but it does look a little old and brittle. Do i just replace the sensor? Does it just pull out from the hub?
Jon_Bmw
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Mon Jun 29, 2009 1:08 pm

Are you sure you are measuring the right part of the connector? To not give any resistance on all of them is unlikely. I am sure you are, but just to check, you are measuring the sensor side of the yellow plugs rather than the ABS ecu side?

They should read around 1000ohms and anything substancially different is likely to indicate a fault.
kman82
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Mon Jun 29, 2009 1:12 pm

yeah mate, sorry probably not made that very clear. I checked them all sensor side in the connector. Back two and front right all measure about 1100 ohms. Front left gives no reading at all
Jon_Bmw
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Mon Jun 29, 2009 1:17 pm

Sorry, I have read your post properly now. :eek: It was perfectly clear, except it didn't account for an idiot like me. :)

Yes the front left is the sensor that normally goes in my experience. I suspect its because its the NS and collects crude in and around the ABS ring and sensor. As it is reading open circuit you are pretty much guarenteed you need a new sensor, expect to pay around £10-20 for a second hand one and probably approaching £100 for a new one. 8O

They are held by a simple allen key bolt and just pull out. It is worth cleaning the ABS ring as well, whilst you are grovelling about underneath.

After a 'new' sensor is fitted there is no reset procedure or anything like that.
Jon_Bmw
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Mon Jun 29, 2009 1:19 pm

If you have time on your hands you could check the wiring to the sensor to make sure its not fractured, but for the hassle its usually worth just getting another one off one of the reputable traders off here.
kman82
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Mon Jun 29, 2009 1:32 pm

Righty. I'll try and acquire a 'new' one then. thanks
kman82
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Mon Jun 29, 2009 1:37 pm

Another quick question.... Will any age ABS sensor work with my 88 325i cabby? I believe its pre facelift and may have the early ABS ecu. Are they interchangeable
Jon_Bmw
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Mon Jun 29, 2009 1:49 pm

Check

'realoem' google search it.

This will show if there are different sensor part numbers. I would be suprised if they differ.
kman82
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Mon Jun 29, 2009 2:04 pm

I've been searching on there all morning for the sensors but cant find them.
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Brianmoooore
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Mon Jun 29, 2009 2:25 pm

No age related change in the sensors, AFAIK. The old and new ABS ECUs are interchangeable as well, although an early one fitted to a late car might fall victim to a voltage surge at some time.
ABS sensors 'just pull out' in the same way that rear beam bushes do! Some might come out easily, but others will have effectively welded themselves in position!
Jon_Bmw
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Mon Jun 29, 2009 3:27 pm

I guess a little persuasion on the tab(with the bolt through it) might be the best way. A sideways tap to shock it, then try and extract it. Sounds like I got lucky 3 to 4 years ago!
kman82
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Mon Jun 29, 2009 6:51 pm

hmmm. 'effectively welded' doesn't sound great. We shall wait and see, i'll wait until i get a replacement sensor before i try persuading. I'll keep you posted
kman82
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Wed Jul 08, 2009 1:58 pm

Just a quick update, a bought a second hand sensor off ebay from a '91 325i for £13 and fitted it this morning - no more ABS light!!
Jon_Bmw
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Wed Jul 08, 2009 2:31 pm

Good result. Just think, for a garage to do that, you'd be on the thick end of £150.
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