ECU question

[C70 98]

I need a new ECU, but the question is what numbers do I go by?

Picture 1 is the ECU in the car now, question is, can I replace it with the one I've found in picture 2? Car in question is a 1999 c70 T5 manual.

[Volvofreak2]

Hej,

you don´t tell us, what modelyear you drive. The partnumbers are the same, so it should fit, and I assume, your Elk is modelyear 99. But, if this is the case it won´t work, because from this year on, the Elks had a electronic throttle, that is married to the ECU. In this case, you have to change this either!

Hej hej Gernot

[volvo again]

Not 100% sure, but I don't think swapping an ECU will be a plug and play matter...
May need to be programmed by Volvo...

[C70 98]

Thanks for the replies, mine is a -99 T5, with the ETM. It's been acting up when warm, cutting out and ETS, EML and oil lights have flickered, no fault codes, it has been diagnosed at the main dealer as a faulty ECU.
They say I need one from a car with the same engine and same model year, oddly enough they didn't know the part number for it. Once I got the part number for it, there are plenty of them around, just not from a -99 T5, with a manual box, if that matters.

I presume any programming could be done by the main dealer.

The one in picture 2 is from a 03 diesel, according to the scrappie, no idea if it will work, but it is the same part number and several other numbers as well.

[volvo again]

Are you absolutely sure the fault is the ECU and not the ETM, there are various companies that can repair the etm with contactless parts.

Just because the ECU has the same part number, don't assume it will work. As you know the ECU controls the entire engine management and any other ecu may be set to different parameters...

[Volvofreak2]

Hej,

if the ECU on the second picture is out of an diesel, it will work in no way. You need one of an identical engine, as all parameters for the engine are programmed in the ECU. It may be able to programme one, but Volvo wants so much money for the software that this is not interesting, especially when there are plenty ECU´s from a T5 are available.
I also would follow volvo again and recommend to midify the ETM to contactless. At least one possible troublemaker less.

Hej hej Gernot

[C70 98]

The ETM is swapped for a contactless one, among the first things I did when I got the car

It is 99% certain that the ECU is the problem, or at least should be as it's been diagnosed by the ones who built the car. I've read that you can clone the ECU to another one of the same part number, and I've also read that you cannot swap them straight over as the immobiliser and other stuff is coded into them, even if it's the same engine, year and part number. Not sure what to think really, but I believe I will try the cloning as there's a tuning company nearby that would be able to clone the thing.

[Volvofreak2]

Wish you good luck! Please let us know how it worked.

[C70 98]

Thanks, will let you know how it goes.

[960kg]

The last three digits have to ideally be the same *******559 otherwise some accessories on the car may not work eg: heated seats...A/C...electric roof?

You see in the pic which is only part of the full list you will see underlined your motor and those underneath are the same motor but different numbers as the customer built and even engine is different.

Having the incorrect ECU could even give the wrong ignition timings and turbo pressure for the engine?