Very strange electrical troubles!

[rob2859]

Hello guys, I am a new member but a well known member of 206info.co.uk. I have been having some very strange electrical issues. I need the help of some experts please.

I am going to explain as best I can as to what is going on. It has happened over a period of time.

Firstly a long time ago I noticed my back wiper still worked without the fuse in; strange and quite impossible but I turned a blind eye.

Then I noticed that the dash lights would come on after the ignition was left on for a long time. The STOP and petrol lights would flash, see picture bellow.



A concern but I turned a blind eye.

A long time after that the EML light came on so I went for a diagnostics. I had this done twice.

Readout

P0481 Cooling fan control circut - Nothing wrong with the fan it comes on when it should.

P0606 ECU - ????

P0268 Injected fuel quantity cylinder 3 too high - Coil pack? MAP sensor?

P0325 Knock sensor 1 (Bank 1) - ????

P0606 ECU - ????

Then one night the car dropped onto 2 cylinders. I know a lot about mechanics and tried everything I could but I had no joy.

I took it to an auto-electricians and they found a wire on the o2 sensor that had broken which I had missed. They repaired it and it went back onto all 4. (How this caused it I don’t know)

The car was still over-fueling and the guy seemed to think the ECU was ruined.

Around the same time as this the battery would occasionally go flat; when it did the car seemed to have some kind of fit, see videos bellow.

Video0017.mp4 video by Rob2859 - Photobucket

Video0011.mp4 video by Rob2859 - Photobucket

The power cuts out on second ignition meaning jump-starting the car didn’t work. However there is power (lights flashing, beeping and relays clicking) when the key is out or in the off position. The second time this happened I notice the electric windows and central locking had stopped working (totally).

I realized then why the battery was going flat in the first place (although not what caused the fit). It was because the dash lights (like before) and the headlights would come on randomly after a long period of time. Sometimes they turned themselves off again.

It started doing this more frequently, then it started doing it every time after the car was left alone; immediately after the BSI shut down, now the problem would not turn itself off. I also noticed that the temporary live on the radio had become a permanent live by itself when I changed my radio.

Now I had sourced a second hand ECU with the BSI and transponder to match. I set about replacing the ECU to fix the earlier problems.

After that it seemed no issues had been resolved apart from the over fueling. Now the Airbag, STOP and brake light are on all the time when driving which did not happen before, also the speedo was not working.

The EML light came on again and the speedo has not worked since swapping everything over so I took it for another diagnostics.


Instrument Cluster memory:

Speed signal signal improbable: Speedo
Control unit for central electrical system no communication - Comms unit faulty?
Data line no communication - Comms unit faulty?
Coolant temp signal improbable - Needle is fine but could explain the stop light?

Central electronics:

Communication between central ECU and ABS/ESP communication faulty? - Explains the dash lights
Air con evaporator temp sensor open circuit - Similar reading before with the old ECU

ECU IAW 4.8P:

Cooling fan power/ground circuit - Similar reading before with the old ECU
A/C pressure sensor signal too small - Similar reading before with the old ECU
Synchronisation of camshaft (bank 1) to crankshaft signal improbable - Don't see how this is related?


I have now found it I remove the fuse for the MF Display and the boot light then it stops the dash lights and the headlights coming on. Apart from very occasionally when the ignition on left on for a while.

However the items that use that fuse still work without it being in :S

I tried to fix my electric windows and central locking but failed. There is no live feed to any of the plugs in the doors or the window switch and I couldn't trace them back further.

This is as far as I have got now, I really am clueless. What the hell is going on?