C8 Power Steering

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David_M
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C8 Power Steering

Post by David_M »

Hi, new to this Forum.
I have recently bought a 2005 Citroen C8 Exclusive 2.0hdi with only 81k, had an airbag fault, I found this was a broken spiral ribbon cable in the COM2000 unit.
Repaired ribbon and no more airbag fault, yay!
BUT, now I have THE ASR Light saying angle sensor, and i have a basic scanner an Autel Maxidiag elite, which you can see the steering angle in degrees on live data, at forat, it was working the degrees were chamging as i rotated the steeringwheel, BUT, next time i checked, the degrees were stuck solidly at 3267° no matter how much i turned the wheel!?
, tried to get it calibrated today atvthe diag specialist I've known and used for years, his scanner says "communication error" (3 different scanners said this btw) and again, the angle readout on live data shows no movement at all, it is stuck on something like 3267°!?
This post could be what's wrong with mine, i.e. no power to pin 4 of the 6 pin black socket to the back of com2000 unit, I've yet to test.

Does anyone have any ideas otherwise as to why I have this issue? And what you would try based on the above info?

Thanks so much!

David.
wheeler
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Re: C8 Power Steering

Post by wheeler »

Sounds like something has been disturbed or damaged during the replacement of the ribbon cable.

I would think the pin numbers from the diagram should be the same as the one above, at the com2000 side at least.
David_M
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Re: C8 Power Steering

Post by David_M »

Hi again, well I soldered 6 of the 7 wires of the ribbon cable spiral to where it joins at the main unit end (cable was from another com2000 which didn't work with my car) anyway, 1 of the 7 wires (copper strips) (3rd from the left) did not seem to have a soldered joint to go to, it just fell away as I was doing the others, so I left it unsoldered as I couldn't see where it would go. I thought, well, 6 wires (2 for stage 1 airbag, 2 for stage 2, & 2 for horn =6) BUT I'm now wondering whether this 7th wire is actually used now I have ASR Fault(Steering Angle Sensor) that cannot be cleared or the SAS Calibrated. Scanner says " Steering Angle Sensor internal fault" which has only happened since i finished off the spiral cable by pulling the remaining bits of the spiral cable at the coiled/moving end of the ribbon cable that was hanging on by a thread. Thing is tho, I haven't even disturbed the SAS as that is a separate part from what I was repairing.
So my question is, does anyone know what each wire does on the 7 wire spiral cable?
Are All 7 Used, or just 6, like I thought? Thanks alot 😊
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GiveMeABreak
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Re: C8 Power Steering

Post by GiveMeABreak »

The SWAS is integrated into the clock spring assembly. These are very sensitive and have to be recalibrated if removed using the pro diagnostics tools like Lexia / Diagbox. If it cannot be calibrated using the above, then somethings not right. Pop the VIN up and I'll get a specific diagram up for this vehicle in case there are any differences. Please post your VIN in full without spaces - it will be automatically masked from public view after submitting your post & will only be visible to staff.
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Marc
David_M
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Re: C8 Power Steering

Post by David_M »

Hi thanksnso much for your reply again.
VIN is: VF7**************[VIN obfuscated, can be read by forum staff]

Also, I have just looked on ither forums and 2 different threads have said about having to drive perfectly straight for 100 metres BEFORE even starting calibration, or it won't work, and someone had my same code (C1135) until they finally calibrated successfully. I thinkvtgis "internal fault" code of C1135 is something of a red herring, by giving the impression something needs repairing/replacing when really it just needs calibrating? I have tried 2 people to calibrate and neither did that (drove 100m straight on even ground BEFORE starting the calibratin procedure) , they even turned the steering wheel from the get go to avoid other cars / obatacles THEN stopped and started the calibratuon /straight drive at what they thought was 100m, and both garages went over speed bumps or choppy ground too as that is all that is around therir immediate vicinity but way before 100m was reached their scanners said communication error / fail or something I'm not 100% on exactly what it said.
I don't think they had Lexia or Diagbox either just Autel and Snap-on scanners. Does it HAVE to be Lexia/Diagbox?
Thanks.
Msig
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Re: C8 Power Steering

Post by Msig »

If you are getting a communication error and no live data from the SWAS, it's a very good chance it's another fault and not due to it being uncalibrated.
I have a lexia and before I found out exactly what my fault was, I tried dozens of time to calibrate following the 100m method thinking it was just a calibration issue, reading similar forum posts.
But every time it just said communication fault.

Once I had supplied power to mine whilst poking around, I had live data and I calibrated on my drive not having moved for hours. I just made sure my wheels were straight.
David_M
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Re: C8 Power Steering

Post by David_M »

Hi, thanks for reply, I'm out my depth on this one! I have tested power from supply wire to pin 4 (yellow wire) to the black 6 pin connector at the back of COM2000 to SWAS. That's as far as I've gone. I just don't get it, I didn't take apart or mess with the SWAS, apart from unplug it obviously, I only worked on the spiral ribbon. Didn't drop anything, I was very careful.
This other COM unit I got from the scrappy, (that isnt programmed for my car hence throws up CAN errors, kicks off the alarm and immobiliser / no start)
Well I plugged that in just to see what that SWAS was saying and the degrees on that are stuck on 0°. Whereas the degrees on my original one is over 3000° and also doesn't move.
Thanks.
David_M
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Re: C8 Power Steering

Post by David_M »

I don't know how to test the other 3 wires (earth, and CAN high & low)
wheeler
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Re: C8 Power Steering

Post by wheeler »

Just to confirm, are you checking the power at the 6 way BLUE connector?
David_M
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Re: C8 Power Steering

Post by David_M »

Sorry yeah the blue connector, which goes into the black socket directly onto the back of the SWAS PCB.
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GiveMeABreak
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Re: C8 Power Steering

Post by GiveMeABreak »

I've split this thread off into a separate topic being it is unrelated to the Xsara Picasso Thread.

Not much help, but this is for the comms unit and it's interaction with the ESP System:

Image
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Marc
David_M
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Re: C8 Power Steering

Post by David_M »

Thanks for that, yeah I should've really started a new topic rather than post on an existing one, nice to see it was only a couple weeks old tho, usually they're 5-10 years lol.

Thanks also for the schematic, although tbh I really wouldn't know where to begin with it!

I just need to know how to test the other wires to the SWAS but my troubles began when I opened up the com unit so looks like I'll need another one now even though I fixed the airbag ribbon wire break, my reward was to cause another issue with ESP to replace it!
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GiveMeABreak
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Re: C8 Power Steering

Post by GiveMeABreak »

That's usually the way it goes - these things once removed will need recalibrating again - I've done it several times in past year and got caught out. I got it calibrated at my dealer years ago on a C5 when this happened to me.
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Marc