Airbag ECU - The Mystery

[Glennst]

Morning all,

You may recall from my previous thread that my 2003 Megane Hatch is in for repairs, to remove the illuminated airbag light. Well, long story short, the airbag ecu had crash data on it and despite several attempts to remove the data (by an auto electrical specialist) I have been told it is corrupt and must be replaced.

The existing ecu part number is: 8200 257 046 E

Both myself and the mechanic have searched the earth looking for a second hand or reconditioned ecu with the same part number, and we simply cannot find one.

I contacted Renault UK and they couldnt find anything under the part number either, and so asked for my chassis number. They then told me that the airbag ecu for my car is part no: 8200 257 049 E, with the last digit being the only difference. My question is, how is this possible ?

Renault quoted me £120 for the ECU, fair enough I thought, but then £70 EACH for two connectors that I apparently need to complete the package. My electrician says that he only needs the ECU, if I can find the exact same part number, as this will remove the need to re-programme the whole system.

I am confused, and unsure what to do next.

Why can neither the iternet or Renault find a replacement ECU with the same part number that I currently have ? And if I buy the replacement part with a slightly different part number will it simply plug and play ?

Any experiences welcome.

[tomalamix]

he doesn't need to reprogram the ECU? if the ECU is not coded to your car even if the ECU had the same P/N it would need to be programed, unless you have the mega luck to know that the ECU from where youre getting it is EXACTLY the same car as yours, same extras, same features, same everything..

[davelowe]

Tom,

I don't for one second doubt what you say, but where did you learn this information?

The reason I'm confused is that the OP says 'airbay ECU'. As I understand things, there is an inertial system with a control unit that triggers the air bags which is under the passenger seat or centre console and is quite different from the engine ECU. Whether this distinction is useful, I'm not so sure!

[tomalamix]

i suppose that the poster are talking about the ECU and not the inertial or accelerometer, whatever people want to call it, because that unit only determines if the de-acceleration applied on the car are enough to trigger the airbag, but the final call is not made on this unit, is made on the ECU (or UCH - i dont know the renault philosophy for this), because the car speed, car stopped or not, seat occupancy among other variables are important to trigger on not to trigger the airbag.

if the problem is not the ECU (or UCH) then the inertial unit is the part we are talking about? if it is it doesnt need to be "coded" in the proper mean of the word but the car crash history must be reset (on the ECU or UCH) to enable airbags again after changing the worn parts...

i think ive explained my self this time...

cheers

[Skidms9]

The likely reason you can't find a reference to your original part number is because parts get superceded all the time for new ones and each supercession means a new part number. I personally don't know of a superceded airbag ecu that requires new connectors but i'll check the number you listed above and see what's what. If you want, pm me your vin and i'll look it up for you.

[ikhan]

Have you actually seen the part / part number? It could be that he wrote the last digit down wrong - simple mistake to make