Merc A140 ECU question

Just read in Haynes manual for the Merc A140, that if the ecu is removed (disconnected from its connector) that "...it must be reconfigured by a Mercedes dealer". Is this correct? I thought most s ecu's just "re-learn" the various data maps as soon as driving starts.

Reply to
dave
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It might just be some form of theft protection?

Reply to
Dave Plowman (News)

Don't know about Mercs, but VAG engine ECUs are paired with the immobilizer (in the instrument panel), so while removing the ECU and refitting it to the same car is OK, putting it in another won't work.

Reply to
Chris Bartram

It's not called the "Book of lies" for nothing. Only NEW ECUs need coding to the car.

If you ever need it fixing - seems to be shockingly common.

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Could be worse like W124 inner wing rust at c12 years old.

W210 ....

There was a time when MB were noted for being bullet proof but that was a long time ago.

Reply to
Peter Hill

The air mass meter is part and parcel of the ECU (yes, crazy design) and often fails. Therefore the new AMM comes with a new ECU which obviously needs pairing with the immob and keys.

Possibly the worst car ever made, both to drive and maintain. Period.

Tim..

Reply to
Tim

Would you have to pay a dealer every time your battery went flat, or when you had to replace it?

Reply to
alan

oddly enough the idea of that came to me yesterday when I disconnected a battery, it would be trivial to add in some instruction that meant the ecu needed a code if power was lost, just like a radio. and only a dealer with specialised equipment could reset it.

Reply to
Mrcheerful

Some early versions of the Rover 820 needed dealer attention to reset the ECU if battery power was lost. Failing to do so would mean an idle that was so poor it would fail an MOT on emissions.

Chris

Reply to
Chris Whelan

If that was the case then thats just piss poor design;!...

Reply to
tony sayer

Merc A140 ECU+MAF seems to have quotes around £1000-£1300. £200+ for your coded ECU repaired. German car, French Valeo electronics. What do they expect? Payback for the crap "frog export" grade stuff that Bosch sold to Citroen for the BX.

Built in message "you WILL scrap this car when it's 12 years old". First battery change at 6-7 years old will get a reset done by a main dealer as the 2nd owner still thinks it's worth the cost and wants to flog it.

Reply to
Peter Hill

Use a power saver keeps the circuitry live whilst battery is being changed

Reply to
steve robinson
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Doesn't help much if you've left your lights on, or the battery fails significantly overnight however.

Chris

Reply to
Chris Whelan

Early Single point injection flavour as i recall.

Tim..

Reply to
Tim

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