Mare of a time with my ABS light!

[Z3I]

Well, I have to say I've had a great time with the Zroadster.org team rebuilding my front and rear suspension, steering, bushes over the winter, and have to say its worked out well! Car drives really nicely now, and the engine purrs! Bliss!

Except, the ABS light.

Hmm..why wont it behave? Generally when I start the car up, it always comes on, and stays on. But after a few miles, it might go out. As if its gets warm? Then when I park the car. leave it a while, sometimes very quickly, on starting up it comes on again.

Simultanious with this, the speedo sometimes works, and sometimes doesn't, but doesn't correspond entirely with the ABS light.

So today I bought a new rear sensor. Not sure why, but I thought that this might be the culprit. sadly Ive tried it both sides, but no1 Good initial results, but in the end the light returns.

I bought some diagnostic software, but cant get it to work.

Any ideas!

 

[Antm72]

The Z3 has issues with the abs pump module. You need to get the codes read. The pump is power fed from the module and the joint snaps and cause the light to light.
I had loads of issues with mine tried sensors etc i managed to get a replacement module which turned the light out perfectly but you have to have it coded or the abs will not function.
A code read may answer the question as to whats causing the issue.

 

[Sean d]

I believe the module can be re-soldered, Is this correct @Antm72 , I believe my 2.8 may have the same issue

 

[Z3I]

Yes, a code read I hope will be possible soon. That will help!

Meanwhile to on/off, all ok/not ok is a pain!

 

[Z3I]

By the way, 1 new BMW abs sensor, £100!

 

[Jack Ratt]

You probably wont be able to access the ABS module with a generic code reader on a pre facelift car.
I had the same problems and tried a few members code readers without any success. I eventually got it sorted with help from another forum

Read this article from another forum to what you are going to need

http://www.bimmerforums.co.uk/forum/f99/bmw-inpa-diagnostics-idiots-guide-getting-started-t85220/

Points 7, 8 and 9 are the ones you need to take onboard

 

[Jack Ratt]

By the way, 1 new BMW abs sensor, £100!

I bought a pair of front wheel sensors from German Ebay seller for around £25 delivered and they came with 2yrs guarantee. They've been on the car for over 2yrs now with no problems what so ever

 

[Z3I]

I'll give it s read!

 

[Antm72]

I believe the module can be re-soldered, Is this correct @Antm72 , I believe my 2.8 may have the same issue

Yeah it can be resoldered but you have to cut the casing to get in as its moulded. It can be re manufactured by bba reman or ECU repairs they rework all the electro magnets and resolder, its cheap for them to fully bench test.
I brought an entire numbers matching module from an e46 its been fine. The lights drop striaght out but as said it needs to re programmed but it only cost me £20 and the abs works perfectly.

 

[Dino D]

I’ve had this issue on and off recently and it was ultimately new sensors needed. First the front (which was damaged) and then the rear that just died. I used £40 Bosch ones.

Mines a very early 2.8 and when the mechanic look at the ABS unit he just said unlikely the unit as that was the reliable one but the later ones (as fitted to newer BMW, Golf, Ford etc) fail regularly hence so many companies doing refurbs of them.
I remember yours is also MK1 2.8 but maybe the newer TU model?
Not sure when they changed the unit over.

As mentioned a proper code reader needed to what’s what.

If you know how then changing all 4 sensors is probably a good idea given the sensors do seem to die after 20yrs! (But not at £100 each!)

 

[Z3I]

I've not looked at the abs as yet. Actually don't know where it is!

 

[Antm72]

Its on the passenger side inner wing below the diagnostic port

 

[Jack Ratt]

Your car is a cross over car. You have the M52TUB28 engine, twin vanos. A generic code reader might work on your car. as it might not be fully ADS

 

[Z3I]

Its on the passenger side inner wing below the diagnostic port

Yes, can see the abs unit there, with the fluid lines coming in. Is the control unit attached to it? There is a cable and plug attached to it, is this where the sensing wires terminate?
I tried to remove the plug ladt week, in an attempt to clean it, but could not. What's the trick in removing that plug so I can spray with some contact cleaner!
Thanks!

 

[misterpie]

Recently repaired my mates ABS unit - from a 1.9 pre-FL (late 1998 (T reg)).
- FYI, my early 1998 (R reg) has a different ABS unit - don't have a problem, but it's not the same fix if/when I do.

This thread tells you all you need - https://zroadster.org/threads/abs-asc.12579/ - if you have the same ABS unit.
- You'll need more than contact cleaner ;-)

 

[Antm72]

The module removes with 4 torx bolts no fluid loss its electro magnets over pins. The power cable should just un clip. The resonson for intermittancy is the abs does a self check on ignition if ok light remains out. Mime uses to come on on long right hand bends but power cycle the ignition at stand still and it could be put out just became a pain. i have a pump and module in the shed will get you pics later

 

[Z3I]

I've done a bit more research today, to identify what components I have and where they are, and I think I'm getting on top of it!

Id like to disconnect the cable still, that goes to the control unit, just to rework the pins in the socket, and to check there is no corrosion. I can'

not move this connector. Is the method to pull the black handle at the top upwards, so that it allows the connector to be removed? Does the black handle remove itself from the connector, or just come up a short way? Mine seems to be loose one side, but will not budge the other. Any tips?

 

[Z3I]

 

[misterpie]

You need to undo the torx like screws - on the right of the picture and remove the black box.
@McSwerve took his off - just like yours and I soldered the pins and it's all fixed, so you might be in luck ;-)

 

[Z3I]

You need to undo the torx like screws - on the right of the picture and remove the black box.
@McSwerve took his off - just like yours and I soldered the pins and it's all fixed, so you might be in luck ;-)

I think I'm ok on the torx screws, it's taking off the connection that's my problem. How??? It doesn't move!