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S40 ABS ECM Problem HELP S40-V40

I am having a problem with the ABS brakes on my S40 .

The ABS and Brake warning lights came on just after an axle change (something I am told is not related, but who knows etc) and both the dealer and local shop are not offering much that makes sense except that I should shovel additional thousands (well really $800) into their pockets.

Its not a full time thing, and the lights are not on after start up, and only come on after about 1/2 to 2 miles of driving. I have tested the brakes and the abs is deffinately not working after the light comes on, but does before it lights etc.

At first the dealer cliamed that it was due to the axle change and that the code they received was not detailing where the fault was, but later after questioning from the mechanic who did the axle repair they claim the code is for a faulty ABS ECM.

Issue is that I am not comfortable with this as they told me in person that these rarely go bad and can produce false positive type diagnosis on themselves (the abs ecm) and the fault may lay someware else. Since this is not a $100 repair I dont want to be paying the dealer to play parts swap backyard mechanic.

My questions are 1) does any of this seem to be right? 2) would it make sense to find an inexpensive replacment ABS ECM? ( I think I may have found one) 3) Are any special tools required beyond any programming etc 4) where is this located, and what does it look like?

Any help or ideas are appreciated, and I would really like to get this right because the rest of the car is in decent condition, and no matter if I keep or even more so if I was to sell it I wouldnt want to do that with any brake problems.

Thanks in advance








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    S40 ABS ECM Problem HELP S40-V40

    Try running the engine without driving. Does the light stay out now?
    And when it lights up when you are driving, i'ts defenetly a sensor problem.
    Maybe the have knocked the sensor during driveshaft replacement. When the gap between sensor and sensorring on the driveshaft is to wide, the sensor receives a to weak signal what could the reason for the ABS light to turn on.
    Also check for correct wiring of the sensor and the number of teeth of the sensor ring.








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      S40 ABS ECM Problem HELP S40-V40

      See thats part of the problem.

      The lights will not come on unless the car is driven, and it really makes sense that this would point to the sensor on the axle, but the problem is that the mechanic who did the axle is now hiding behind the dealers claims to him that the abs control unit is coming up as bad on the scan.

      Effectively what has happened is that the dealer has told me one thing (that the codes they are getting are not pointing to one specific sensor etc) and the mechanic who did the job another (that they believe the control unit to be bad) and therefore neither of them is of any help well except if I decide to pay either of them to figure out the mess etc.

      The really sad thing is that I just dont have the time to tear into this myself, and I would really like to just pull the axle or at least take the thing apart and inspect it etc.

      I am damn near positive the problem is in the replacment of the axle, and hate to mess with the other stuff just to try and prove it, but with no help from the guys who installed it being offered it may be the easiest way to the answer other than just selling the whole car (maybe not a bad idea if any of you would want to mess with it, but whats it worth anyhow?)/

      Thanks for all the great replies!!!








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    S40 ABS ECM Problem HELP S40-V40

    Lenny,

    If you send your ABS controller to Victor Rocha, he will repair it for about $150, including postage. Your dealer will sock you for over $600.

    If, however, your controller has not failed, Victor will inform you of that and ship it back to you, and you are only out the postage. Good deal, huh?

    --
    Dave in Virginia; 1998 V70 T5(M): IPD MOTRONIC+ ECU Upgrade, Sport Muffler, IPD Strut Tower Brace, VDO Boost Gauge, IPD Anti-Sway Bars, Koni FSD Struts and Shocks, Rocha ABS Control Unit/// 1988 245 DL Wagon// 1967 MGB Roadster








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      S40 ABS ECM Problem HELP S40-V40

      Quick question.

      The ABS ECM location?

      Is it on the ABS unit under the hood?

      Reason I ask is because I found an entire unit on ebay at a great price, and am thinking it may be worth a try if it includes the ECM

      Thanks again








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      S40 ABS ECM Problem HELP S40-V40

      Thanks all for the valuable info, and I will be checking into Victor etc.

      I think were all on the same page in thinking it is most likely a problem from the new axle install and no one has been willing to actually remove it to even check etc.

      What happened that seems really fishy is what I heard from the local guy about his talk with the dealer. The dealer told him the complete opposite they told me, and basically left me only one option if I was to have this done thru either of them.

      Since they are now claiming that the ecm is deffinately bad and that all sensors checked out ok (before they were pointing to the sensor and hedging their bets with the expensive ecm replacement) the only thing I would have to do is let them change it, and then if there was still problems go after them for a refund etc.

      Only problem is that I have already caught this group mixing up things real well, and I wouldnt be suprized if they changed the ecm and then later charge for changing out the sensor too.

      If anything interesting comes of it I will post it up for reference to future readers, and your potential curiosity.

      Thanks again








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    S40 ABS ECM Problem HELP S40-V40

    I agree with Hybred - it sounds like a damaged sensor if this all started when you had an axle changed. However, if the dealer's kid doesn't need braces, it could also be a coincidence and the ABS ECM may have failed. Your message doesn't indicate the year of your car, but believe the 2000-2001 models were plagued with this problem similar to 96-7 850's. If so, I'd save the extra $650 and use Victor Rocha instead. He did my 97 850, and I imagine he'll be doing my 2000 V40 before too much longer. His web site is http://home.earthlink.net/~vicrocha/ and he comes highly recommended by fellow Brickboarders. Good luck, and keep us posted.








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    S40 ABS ECM Problem HELP S40-V40

    replacing an axle improperly can certainly cause an abs code as the sensors are on the ends of the axles. if you had no code prior to the axle swap and do now it's very possible one of the sensors were damaged during install and they are trying to cover their buts. diagnosing a faulty sensor is quite elementary.







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