Ignition and window opens

[Slo]

Certainly i've learned a hell of a lot lol

Things that can be classed as known issues are...

If your speedo doesnt work because of the drive cog or speed sensor (or its wiring) it will give an airbag warning and disable the roof (which just beeps with no indication why) because the bsi is unable to determine the threshold speed when they can work or not.

On the diag the speed fault gives codes on...

Instrument panel (the actual speedo), abs, airbag system, roof and even the aircon system, giving an intermitent problem. Only the engine ecu was giving a permanent fault code saying it was the wrong signal or short ciruited to earth when in fact it just simply wasnt getting any input at all

[leegsi]

Popped out the new speedo just now after draining what was left of the gearbox oil, thought while it was out id strip off its wiring harness from the lump to where it joins the rest, connect up the old one to it and spin it in my drill.

Well the speedo works like this and I had at least 50mph out of my drill

So that confirms the old speed sensor is fine and ive put it back in and bolted it up, car back together
and refilled the gearbox with 1.9l of 75w-80 oil and guess what?

At that point it pointed to the gearbox drive issue as by using the drill instead of the gearbox drive it all worked,

Atleast you got to the bottom of it

[Slo]

Yes but unfortunately I had the entire engine wiring loom off the car but plugged in both ends so i could manipulate the wires. This did lead me to think that it was the speedo drive as you say as logically it couldnt be anything else as once id put it all back together it didnt work

[andreas]

Hi Slo, thank you for sharing all this information. I have the same problem with my 206 cc from 2004. When I turn on the ignition the side windows go down. I see that you write: "found a blue plug disconnected in the nearside A frame and reconnected it (now drivers window doesnt drop with just ignition on and works properly at all times)". May I please ask where you found this blue plug...was it under the hood or behind the glovebox? Thanks in advance for any details here

[Slo]

Both windows dropping might be down to a poorly roof ecu or damaged wiring. The blue plug i found unplugged behind the glovebox. You can get to the area by popping out the side cover on the dash but its a tight fit. The blue connector goes into the door pillar and into the door loom but it only affected my drivers door window.

[andreas]

Thanks a lot for the details, I will look for it. It is strange, all 4 windows drop when starting the car but works fine for the rest of the trip after closing them. I have replaced the window/mirror switches in the center console without result and hope I will not have to replace the roof ecu. I will post here what I figure out. Thanks again!

[Slo]

You can get a roof ecu for 20 quid off ebay they are all the same for the 206 just do a search for the ecu number, I doubt it will be that but you never know. Something is probably unplugged under the dash.

[Banditboy]

Can a secondhand ecu just be installed and it works how it should or is there a little more jiggery pokery involved?

[IanL]

The roof ECU is plug in and go, no configuration required.

[andreas]

Hi, where is the roof ECU located? Unfortunately I did not find any blue plug behind the glove box, but I see plenty of them on the left side in conjunction with the fuse box. (This is a Norwegian car with the steering on the left side)

[IanL]

In the luggage compartment, on the left side, below the speaker.