Air Bag Ecu Failure - Second Hand Unit Replacement

[Andrewrt]

Newbie post from an oldie - As a result of severe water damage my daughters July 2004 Mini One Cooper has just had second hand BC1, fuse box and air bag control units fitted, and needed a new battery. The SRS / air bag light now stays on permanently, and as is well known is an MOT failure item. I have had the electrics checked out and the second hand air bag unit has failed. I have been quoted £600 for a new unit, fitting and reprogramming. I am told I cannot use a second hand air bag unit - (PN 65.77 6962531 which supercedes 65.77 6933242). My question for the great knowledge base out there is, is this true? I can get a tested and working unit that fits the R52 for less that £100 but will it work, can it be programmed? £600 seems a lot for this. Hope someone can end the wondering.

[Andrewrt]

As a follow up to this post I can now update on progress. I bought (£43 delivered) and fitted a second hand air bag control unit of exactly the same part number as given on the Online BMW parts site (Real OEM). This was different to the one fitted! This second hand unit is also guaranteed for 90 days. I went to my local Ford dealership (nearest place to me with the required vehicle software) who cleared the codes for me FOC! There were 22 codes, I have 4 remaining all of which relate to the side impact crash sensors. I am now sourcing the correct part numbers 65.77 9 120 296 although 65.77 6 914 304 had been fitted originally. It looks like you do not need to re-programme anything in the air bag control unit, there does not appear to be any of the original donor car details stored in the unit. So far I have saved over £500 against the original quote I received. Moral of the story is if you have time do some digging do it and don't take the first option offered.

The crash sensors are not where the manual said they were either and you didn't have to remove the seats to get at them......................... I'll let you know when I succeed in getting rid of the air bag light.

[btmaldon]

Nice one Andrew. Just goes to show what these so called specialists really know.

[Andrewrt]

Final update on this posting! I have now replaced both faulty crash sensors as well as the air bag control unit with second hand 90 day guaranteed units. This was very easy to do. No components needed reprogramming and after the final error messages were deleted the air bag light went out and stayed out. Many thanks to my local Ford dealership who I have to say were incredibly helpful and did not charge me for either reading the error messages or clearing them - this took 3 visits. Final observation is that the air bag control unit is advertised on some used parts sites as an air bag ECU - I think that is misleading as the ECU implies part of the Engine Control Unit which as we all know it is not. Anyway, after an original quote of £600 to £800 it has been done for £98 - MOT next...................... I hope this experience will help someone out there.

[btmaldon]

Thanks Andrew. Its good to know as this is bound to come up for someone else at some point.