urS6 Auto ECU & TCU Location

[s2_wot]

Right folks, I've got to remove the ECU from the S6 and I think it's in the passenger footwell somewhere close to that pesky afterrun relay. Anybody got specific directions and whats this about cutting the carpet to get it out??

Also 'cos I have an autobox (slushbox) I have to find the TCU. Anybody got any ideas where that might be hiding?

Steering wheel is on the proper side (RHD) if that makes any differance!

Pictures etc to follow.

[spink]

Right folks, I've got to remove the ECU from the S6 and I think it's in the passenger footwell somewhere close to that pesky afterrun relay. Anybody got specific directions and whats this about cutting the carpet to get it out??

Also 'cos I have an autobox (slushbox) I have to find the TCU. Anybody got any ideas where that might be hiding?

Steering wheel is on the proper side (RHD) if that makes any differance!

Pictures etc to follow.

yes the carpet needs slitting at the back of the centre console but theres a good chance its been done already,cant say i have ever had to do it on any c4 ive had ecus in and out of(quite a few),when you pull the carpet back you will see 2 black plastic panels,unsrew them and you will see the ecu

box ecu is under rear seat i think

[s2_wot]

yes the carpet needs slitting at the back of the centre console but theres a good chance its been done already,cant say i have ever had to do it on any c4 ive had ecus in and out of(quite a few),when you pull the carpet back you will see 2 black plastic panels,unsrew them and you will see the ecu

box ecu is under rear seat i think

Thanks spink, so if you sit in the passenger seat, is the ecu in front of your feet or to the left or right?

back seat is an easy job same as the s2 so happy days

[spink]

yes directly under the passengers feet

part number is 4A0927156L for box ecu so you dont get confused with any other ecus under back seat

[prj]

Autobox ecu is not under the rear seat.
Shane, I will PM you with pictures and details on how to do this before you rip your entire car apart, okay?

[s2_wot]

yes directly under the passengers feet

part number is 4A0927156L for box ecu so you dont get confused with any other ecus under back seat

Autobox ecu is not under the rear seat.
Shane, I will PM you with pictures and details on how to do this before you rip your entire car apart, okay?

Thanks guys, open heart surgery starts tonight when I finish work.

[mcandmar]

AFAIK Shane there both side by side under the passenger side carpet. Dont remember ever having to cut my carpet to get at the ECU but it is a fiddle to remove the plastic cover. Vacuum line to the ECU dosent have much slack in it either but apart from that its not a big job.

[prj]

The carpet needs to be cut the first time.
But honestly, I have not seen a car with an uncut carpet yet...

Otherwise, yes, they are next to eachother.

[S2central.net]

Its fiddly at passenger side footwell if the carpet needs cut for access but no big deal.

I expect the comment about other controllers under rear seat of S4/S6 is that its a bit like S2 in this regard with boxes for ABS, difflock, airbags and all sorts of odd things depending on vintage and options.

Never had an S4/S6 automatic in my hands so interested to know where the TCU lives - though I suppose a quick search on the US based forums would find a result pretty quickly.

[s2_wot]

Never had an S4/S6 automatic in my hands so interested to know where the TCU lives

you haven't lived!!

Stanley knife, selection of screwdrivers and a hammer, what could go wrong?

[prj]

Paul, It's just above the engine ECU. A bit like the ECU location in the S2, but not shoved so much upwards, so it can be gotten out easier.
I explained everything to Shane, I believe he will make some pics and post them up

[s2_wot]

...

[s2_wot]

How to

Remove this sill thing and open the screws below it and move it to one side.



Then open the screw for this piece of trim and remove it.



Off topic:

This fancy looking red cable is going in the bin:



And this bit of electrical butchery is surely going to cause a headache some day:



Back on topic: My carpet was cut previously so the carpet was easy to pull down like this:





Under the carpet were 2 pieces of plastic. Neither were fixed to anything, so just sitting there. I'll need to look into that before I put it all back together.
Remove the pieces of plastic:



And reveal:



Move some wires out of the way and you see this.



The one with Motronic on it must be the ECU. The one above must be the TCU, the partnumber is very similar to spink's above.

I forgot to take any more shots but the 2 boxes disconnect from everything with relative ease.

Fair play to Dmitri who called me from Estonia to point out some of the above.

ps.. hammer not needed

[S2central.net]

Ahh not so bad then - well done.

[prj]

Btw, that plastic panel with a bunch of connectors in, it should be in place (you can find some bits there, so it slots in).

The two plastic panels are aligned. They both have holes and they go so that the large panel goes up and the small panel goes down, then there are some holes that need to be aligned, and if you look closely, there will be holes in the plastic below those two plates as well and some screw holes.

Well, now that you got those out, comes the fun part. Pray your ECU has sockets installed