ABY/ADU T55 Motronic ECU Pin-out with hyperlinks

[cardcrash]

Well Dave as you asked here is the ECU from my RS2, it appears you already have such a picture, but here's mine nonetheless.

Kit's too broken and in hopeless pain from work to fish out his ECU so you will have to wait for that. Anyway here's mine:

[UrS4boy]

Well Dave as you asked here is the ECU from my RS2, it appears you already have such a picture, but here's mine nonetheless.

Much appreciated Charlie. In the interim, Twoqu (Robin) had posted info that had allowed me to find a 8A0907551C photo. Now what I don't have (nudge,nudge,wink, wink) are clear photos of the OE Boost and timing chips inside your 551C.

[S2central.net]

Why is this important ?Photos of what stickers are on OE chips isn't very interesting surely - it's what's inside them is important.

[cardcrash]

Well, you ask, you get...

[S2central.net]

As regards pin 30 - that 0V reference - I thought from a past life that was a floating / indirect reference point but after a quick test with a DMM on an unmolested ABY ECU I can verify that pin 30 is entirely common with pin 19 and therefore 0V battery earth.

The same goes for pin 48 as the 0V ref for G4 and G28.

Attached pic confirms this from ABY schematic. Note that pin 30 is black / lilac on the ABY.

IMG_3380.JPG

[UrS4boy]

Why is this important ?Photos of what stickers are on OE chips isn't very interesting surely - it's what's inside them is important.

Well I was hoping to see some OE RS2 chip PNs because I've only seen one set and wanted to see another.

Well, you ask, you get...

Yup. Appreciate the effort but obviously somebody has messed with the original chips at some point. No telling what is under those file folder quality labels.



Thanks Charlie.

[UrS4boy]

As regards pin 30 - that 0V reference - I thought from a past life that was a floating / indirect reference point but after a quick test with a DMM on an unmolested ABY ECU I can verify that pin 30 is entirely common with pin 19 and therefore 0V battery earth. The same goes for pin 48 as the 0V ref for G4 and G28.

Ouch. You're doing my head in. I think you're saying that I was right in the first case? Can't be.

[cardcrash]

Yeaha, it's a socketed ECU, handy for mods!

[UrS4boy]

Yeaha, it's a socketed ECU, handy for mods!

As per post No. 6 in this thread, Dave T's (CanadianRS2's) May 1994 build RS2 came with a factory socketed RS2 ECU. Any idea what the build date of your ex-car was? PM me the VIN if you don't know and I will figure out the month. At some point they must have stopped socketting the ECUs but when I don't know. Mid-Feb 1992 for the UrS4s off an Aug 1991 start date.

[varia]

As per post No. 6 in this thread, Dave T's (CanadianRS2's) May 1994 build RS2 came with a factory socketed RS2 ECU. Any idea what the build date of your ex-car was? PM me the VIN if you don't know and I will figure out the month. At some point they must have stopped socketting the ECUs but when I don't know. Mid-Feb 1992 for the UrS4s off an Aug 1991 start date.

i can tell you even the day

[S2central.net]

I have seen plenty of socketed ones too. On the ABY is most prevalent on the crossover period from non-immo to immo.

[S2central.net]

i can tell you even the day

You can tell that from the Bosch sticker codes ?

I always thought the unique number on them was a serial number - never thought it was an encoded manufacturing date.

[varia]

You can tell that from the Bosch sticker codes ?

I always thought the unique number on them was a serial number - never thought it was an encoded manufacturing date.

no Paul, i meant from the vin.

[S2central.net]

Oh right - less interesting then ;-)

[S2central.net]

Ouch. You're doing my head in. I think you're saying that I was right in the first case? Can't be.

I was certain at least one of those reference points was isolated from battery earth but I must have mixed that thought with something else. I was just cautioning that you may have oversimplified something but it looks fine.