Gonzogio

E39 abs control unit fault. 2002 520i

30 posts in this topic

In need of a bit of guidance from those in the know here.

Had the dreaded triangle,abs and brake orange warning lights illuminated last week so took them to my local indy for a diagnostic.

He read the codes and replaced the pressure switch. Lights still lit

He then replaced the brake light switch. Lights still lit.

After further investigation he suspects the abs control unit is on the way out.

So..£250 lighter, thoroughly pissed off and no nearer a solution.

Anyone know of a second hand Abs control unit with dsc available?

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Number one thing to do is get the codes read. It could be a number of things other than a faulty ABS unit. When I hd similar probem last yeat, it turnedd out to be the steering angle sensor, after I recalibrated it using GT1 it has never troubled me since, so get a diagnostic done, maybe a member ives near you who has good diag software?

Sent from my X10i using Tapatalk

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Number one thing to do is get the codes read.

8<

I think you'll find he already did that. ;-)

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Yep, codes read, sensors replaced,money spent.

Trouble is Control units with dsc are very hard to come by. E-mailed BBA Reman.. no reply yet. Gonna try ringing them tomorrow. Tried Parts Gateway , no luck.

There's a few new ones about for around £350 that'll need coding but hoping to find a used one or get mine fixed.

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Sorry, Im reading this on my mobile and Im also daft :-D

Im always suspicious when codes are read and they 'diagnose' expensive fixes/replacements that dont solve the issue.

Good luck anyway

Sent from my X10i using Tapatalk

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I agree with willie mate, 250 down and no closer to being fixed? Call BBA mate and send them your ECU, very common fault on the e39. If they find no fault, it's only a £40 chard for the testing I believe.

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if the units at fault it may give all sorts of false code - mine did but I had a clue that it only did it when hot; when cold it was ok. BBA Reman fixed it for <£150 and only took a few days. Faced with a 2nd hand one for simular money off ebay then I'd rather get the original one fixed and you get 2-year warranty iirc which you wont form an ebay seller....

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Is this fault with the abs ecu an MOT failure ?

if the light is on then I beleive its an MOT failure

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Quick update..

Decided to go the repair route with ECU testing ltd. Quoted me £150 & vat for dsc type. No fee if not repairable, Two year warranty if it is. All packed up and ready to post in the morning.

Fingers crossed. Thanks for the advice chaps.

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that's the same a BBA Reman - no fix, no fee, just the postage.

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if the light is on then I beleive its an MOT failure

So is my E39 going to fail its mot in 2 weeks as it has both traction control and ABS lights lit up?

I think its a sensor as it happened after my discs and pads were replaced and up until today the cruise control was working fine. More money into the money pit!!

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Could the failure of my ABS and traction control also be due to my recent failing alternator/battery problem. The ABS and traction lights were intermittent for months before they remained lit and according to haynes low voltages can cause the system to fail and hence the car disables it. Fingers crossed for a cheap fix!!

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Quick update.. ECU Testing say module is beyond repair, now looking for a used one....*sigh*

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off to the breakers - take the p/n of your with you and find one the same. some say the part needs coding but some seem to get away without any such trouble

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After much deliberation and searching decided to go for a new one from Quarry motors, Bmw specialist and breakers, for £360. Dealer wanted over a grand.

Will have to get it coded though.

Given that they are prone to breaking, decided against a used one.

Apparently it was the pre charge pump circuit that was the problem, Bloody things.

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Excellent service from Quarry, new unit arrived this morning, only ordered it 1pm yesterday.

Will I be able to fit it myself then drive down to indy on Monday for coding or leave it and let them fit it and code it?

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if its just the module that yes you can fit it and it should work - I think the coding issue is so other modules can 'talk' to the abs module but not 100% sure why the coding is there

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ABS should work straight after the new module is installed. ASC/DSC will not work properly before it's coded. The coding tells the unit for example which engine the car has so it can work properly.

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